LESSER LONG-NOSED BAT

US Fish & Wildlife Service

Arizona Ecological Services State Office

Phoenix, Arizona

MAY 1994
LESSER LONG-NOSED BAT

Leptonycteris curasoae yerbabuenae

RECOVERY PLAN

Prepared by:

Theodore H. Fleming

Department ofBiology

University ofMiami

Coral Gables, Florida

Prepared for:

Region 2

U.S. Fish and Wildlife Service

Albuquerque, New Mexico

Approved:

Date:
Disclaimer

Recovery plans delineate reasonable actions which are believed to be required to recover and/or

protect the species. Plans are prepared by the U.S. Fish and Wildlife Service, sometimes with the

assistance ofrecovery teams, contractors, State agencies, and others. Objectives will only be attained

and funds expended contingent upon appropriations, priorities, and other budgetary constraints.

Recovery plans do not necessarily represent the views northe official positions or approvals ofany

individuals or agencies, other than the U.S. Fish and Wildlife Service, involved in the plan

formulation. They represent the official position ofthe U.S. Fish and Wildlife Service ~niy afterthey

have been signed by the Regional Director as approved. Approved recovery plans are subject to

modification as dictated by new findings, changes in species status, and the completion ofrecovery

tasks.

Literature citations should read as follows:

U.S. Fish and Wildlife Service. 1995. LesserLong-nosed Bat Recovery Plan. U.S. Fish and Wildlife

Service, Albuquerque, New Mexico. 45 pp.

Additional copies may be purchased from:

Fish and Wildlife Reference Service:

5430 Grosvenor Lane, Suite 110

Bethesda, Maryland 20814

301/492-6403

or

I -800-582-3421

The fee forthe plan varies depending on the number ofpages ofthe plan.

Cover art donated by Mr. Donald Harrington, Phoenix, Arizona
EXECUTIVE SUMMARY

Current Species Status: The lesser long-nosed bat is listed as endangered throughout its range in

the United States and Mexico. There is no designated critical habitat. Scientists familiar with the

species disagree on the present population sizes ofroosts. Recent surveys by some scientists indicate

that at least 60,000 individuals ofthis species may reside and feed in the southwestern U.S. (Arizona

and New Mexico) during the summer and that its numbers throughout its range in the U.S. and

Mexico appear to be greater by one or two orders ofmagnitude than estimated in 1985. Other

scientists believe these figures are too high.

Habitat Reouirements and Limitini~ Factors: Suitable roost sites and extensive populations of

columnar cacti and agaves are critical resources for this bat. Several ofits maternity roosts or other

roosts are currently under protection in Arizona and in Mexico. Columnar cacti and agave food

plants have some protection in Arizona but not in Mexico. Protection ofall known roost sites and

food plants within a radius of50 miles (81 kin) around known roosts will help to prevent this species

from going extinct. Protection offood resources along migratory pathways may also be important

to the survival ofthe species.

Recovery Objective: Reclassification to threatened

Recovery Criteria: TheFish and Wildlife Service should review the status ofthe lesser long-nosed

bat to determine ifreclassification to threatened is warranted ifall the following criteria are met: (1)

each major roost population in Arizona and Mexico is monitored for at least five years; (2) the results

of that monitoring show that population numbers are stable or increase over the higher set of

population figures appearing in this recovery plan; (3) sufficient progress has been made in the

protection ofroosts and forage plants from disturbance or destruction; (4) no new threats to the

species or its habitat have been identified orthere are no increasesto currently recognized threats;

and (5) the Service determines the species is no longer endangered.

Actions Needed for Recovery

:

1. Continue protecting roost sites and evaluate the need for and implement protection for food

plants.

2. Monitor all major roosts in Arizona, New Mexico, and Mexico once a year.

3. Continue surveying for additional roosts in the U.S. and Mexico

4. Develop and conduct a public education and information campaign in Arizona, New Mexico,

and Mexico on the beneficial aspects of bats in general and the lesser long-nosed bat

specifically.

5. Conduct critical research on population censustechniques, physical requirements for roosts,

foraging ranges ofroosts, reproduction and mating systems and other life history and habitat

questions.

ii
Costs (thousands of dollars)

Year Need 1 Need 2 Need 3 Need 4 Need 5 Total

1996 91 75 20 12 45 243

1997 91 65 20 12 40 228

1998 76 50 20 4 50 200

1999 81 50 20 4 50 205

2000 81 50 20 4 30 185

Total 420 290 100 36 215 1061

Date ofRecovery: Ifthe recovery criteria can be met, down listing to threatened may be possible

by 2000. Delisting criteria will not be developed until afterthe species has been down listed to

threatened.

iii
TABLE OF CONTENTS

Page

I. TNTRODUCTION 1

Description 1

Distribution and Seasonal Movements 2

Habitat Requirements 5

Foods 7

Population Ecology 10

Present Status 16

Reasons for Listing 19

Conservation Measures 21

II. RECOVERY 24

Objectives and Criteria 24

Step-down and Narrative Outline 25

Narrative Outline for Recovery Actions 26

III. LITERATURE CITED 31

IV. LIST OF CONTACTS 35

V. IMPLEMENTATION SCHEDULE 37

VI. APPENDICES

Appendix A: Public Review 39

Appendix B: Letters ofComment 40

Appendix C: Responses to Comments 41

iv
List ofTables

Table 1.

Other species ofbats known to roost in the same cave

or mine with Leptonvcteris curasoae yerbabuenae. 6

Table 2.

Major food plants ofLeptonycteris curasoae yerbabuenae. 9

Table 3.

Estimated sizes ofsome known roosts ofLeptonycteris curasoae

yerbabuenae in Arizona and Mexico in 1992-93. 12

List ofFigures

Figure 1.

The geographic distribution ofLeptonycteris curasoae yerbabuenae

,

based on Arita (1991). 3

Figure 2.

Major roosting sites ofLeptonvcteris curasoae yerbabuenae

in Arizona. 4

v
1

I. INTRODUCTION

The lesserlong-nosed bat, Leptonycteris curasoae yerbahuenae, is a nectar-, pollen-, and fruit-eating

bat that migrates seasonally from Mexico to southern Arizona and southwestern New Mexico.

Primarily associated with dry habitats in Mexico and the southwestern U.S., this bat pollinates

flowers ofspecies of columnar cacti and paniculate agaves and disperses seeds ofcolumnar cacti

species throughout its range. Surveys in Arizona and Mexico conducted in the mid-1970s through

1985 revealed low numbers ofthis bat in known roosts. This information led to the species being

declared federally endangered by the U.S. Fish and Wildlife Service in 1988 (Shull 1988). No

critical habitat was proposed or designated for this species.

Since the listing ofthe species in 1988, considerable controversy has developed between members

ofthe scientific community familiar with the lesser long-nosed bat. Information on population size

(both at the time oflisting and at present), accurate census techniques, total range ofthe bat in

Arizona, and the importance ofthe species to the successful reproduction ofvarious columnar cacti

and agave species has been questioned and debated in public forums. This lack ofconsensus among

the scientific community causes difficulty in defining the status ofthe species and determining

appropriate downlisting criteria.

-The Service has not taken a position on the divergent viewpointsthat exist between the scientists.

However, the Service does deferto the expertise of our contractor for this recovery plan as regards

the biology and habitsofthe species. Where appropriate, this recovery plan doesidentify where data

or other information is questioned by another ofthe scientists involved. It is because ofthese

disputes that additional information on the biology and population size ofthe lesser long-nosed bat

must be obtained before any reconsideration ofits status as an endangered species can be considered.

Description

The lesser long-nosed bat is one offourmembers ofthe tropical bat family Phyllostomidae found

in the United States. It was formally separated from the greater long-nosed bat (L. nivalis) as a

distinct species (L. sanbomi) by Hoffmeister (1957). L. nivalis is a monotypic endangered species

that occurs in Mexico and southwestern New Mexico and Texas. Arita and Humphrey (1988)

reviewed the taxonomic status of bats ofthe genus Leptonycteris and concluded that L. sanbomi is

conspecific with L. curasone ofnorthern Venezuela and the Dutch Antilles. They recognized two

subspecies ofL. curasoae; a northern subspecies (L. c. yerbabuenae = L. sanborni) found in Mexico

and southern Arizona and New Mexico and a southern subspecies (L. c. curasoae) found in northern

South America. Wilkinson and Fleming (1995) have confirmed the genetic distinctness ofthe two

subspecies of Lcurasoae and the specific distinction between Lci.irasoae and L~niva1is using

molecular data. Unless otherwise noted, any reference to Leptonycteris or L. ctirasoae refers

specifically to the endangered L. curasoae yerbabuenae.
2

The lesser long-nosed bat is a medium-sized bat with forearm measuring 51-56 mm and weighing

20-25 g as an adult. Adult fur color is grayish to reddish-brown; juveniles have gray fur. Its

elongated rostrum bears a small, triangular noseleaf, its ears are relatively small and simple in

structure, and it has a minute tail. It is generally smaller in external and cranial measurementsthan

L. nivalis, and the two species consistently differ in the length ofthe terminal element ofdigit III

(<15 mm in curas~ae,> 15 mm in nivalis). L. curasoac can be distinguished from the Mexican

long-tongued bat (Choeronycteris mexicana), with which it co-occurs in Arizona, by its larger size,

less elongate snout, and tiny tail ofL. curasoae.

Distribution and Seasonal Movements

The lesser long-nosed bat has been found in southern Arizona from the Picacho Mountains

southwest to the Agua Dulce Mountains and southeast to the Chiricahua Mountains, in far

southwestern New Mexico in the Animas and Peloncillo Mountains, and south from Arizona and

New Mexico throughout the drier parts of Mexico, including Baja California (Fig. 1). Occasionally,

individuals have been reported outside ofthis range, for example there are records ofindividuals

from the Phoenix area and the Bill Williams River during July and August. It is a seasonal resident

in Arizona, usually arriving in early April and departing in mid-to-late September. However, it has

been seen visiting hummingbird feeders in Tucson in January and February in recent years (R.

Sidner, pers. comm.). It apparently resides in New Mexico only from mid-July to early September

(Hoyt et al. 1994).

Cockrum (1991) collated all published records ofthe lesser long-nosed bat in Arizona and noted that

its distribution varies by sex and season. Adult females, most ofwhich are pregnant, and their recent

adult progeny are the first to arrive, and they form maternity colonies at lower elevations near

concentrations offlowering columnar cacti. At least three such colonies containing 3,500 to 15,000

adults are known to occur seasonally south and west ofTucson (Fig. 2). After the young are weaned,

these colonies begin to disband in July and August, but some bats remain in these roosts into

October. Numbers of bats in late summer post-maternity or “transitory” roosts increase as the

maternity colonies break up, but the specific origin ofthese bats is not certain. Adult males are

known mostly from the Chiricahua Mountains (e.g. Buckalew Cave prior to 1969 and Hilltop Mines

in recent years) but also occur with adult females and young ofthe year at maternity sites (e.g.

Bluebird Mine and Copper Mountain Mine). Cockrum (1991) reported that males arrive in Arizona

later than females, but recent observations at the Hilltop Mines in East Whitetail Canyon near

Paradise indicate that some adult males are present there in late April and early May (C. Rau and T.

Fleming, unpubl. data). Both adult males and females have been netted in August in the Animas

Mountains ofNew Mexico (Hoyt et al. 1994).

Based on the geographic distribution of mitochondrial DNA (mtDNA) haplotypes and other

evidence, Wilkinson and Fleming (1995) postulated that individuals of Leptonycleris migrate into

northern Sonora and southern Arizona along two migration routes. Bats arriving in the spring and

forming maternity colonies in coastal Sonora and southwestern Arizona probably migrate along the
3

Figure 1. Thegeographic distribution ofLeptonveteriscurasoae yerbabuenae, based on Arita

(1991). Stars indicate locations ofmajor maternity roosts. Solid circles indicate

non-maternity roosts. Roosts are: I Bluebird and CopperMountain Mines, 2 Old

MamnionMine, 3 Pinacate Cave, 4 Patagonia Bat Cave, 5 Hilltop Mines, 6 Tajitos

Mine, 7 Cueva del Tigre, 8 Sierra Kino-Isla Tiburon Caves, 9 Santo Domingo

Mine, 10 Isla San Andres Cave, 11 Cueva “La Mina,” 12 Gruta Juxtlahuaca, 13

Cueva “Rancho Tempisque,” 14 Cueva “La Capilla” - San Antonio Mine, 15 Cueva

Mulege.
4

3?

1!

‘3

12

12

24 “0 ‘C

Figure 2. Majorroost sites ofLeptonveteris curasoae yerbabuenae in Arizona. Sites 1-3 are

maternity roosts; sites 4-9 are post-maternity roosts. Roosts are: 1 Bluebird Mine,

2 Copper Mountain Mine, 3 Old Mammon Mine, 4 Patagonia Bat Cave, S

HilltopMines, 6 Box Canyon Crevice (possibly a maternity roost), 7 Manila Mine,

8 State ofTexas Mine, 9 Cave ofthe Bells.

I,. tas is) SI. ISO Set

Depar~ien~ of Biological

Universicy of Arizona
5

west coastofMexico from asfar south asJalisco (a distance of 1,000-1,600 kin). Bats arriving later

in the year and occupying transitory roosts in south-central and southeastern Arizona probably

migrate along the foothills ofthe Sierra Madre mountains, again from as far south as Jalisco.

Habitat Requirements

Two sets ofresources, suitable day roosts and suitable concentrations offood plants, are critical for

the lesser long-nosed bat. Caves and mines are used as day roosts. Factors that identify potential

roost sites as being “suitable” havenot yet been identified, butmaternity roosts tend to be very warm

and poorly ventilated, at least where the young are actually raised. Such roostsreduce the energetic

requirements ofadult females while they are raising their young (Arends et al. 1995).

Fleming has visited many Leptonycteris roosts in Arizona, Mexico, and Venezuela and found the

lesser long-nosed bat living in caves and mines displaying a variety ofmicroclimates (e.g. dry and

hot, wet and hot, dry and cool, and wet and cool). It is found in well-ventilated caves as well as

those that are poorly ventilated and filled with strong ammonia fumes. In Mexico and Venezuela,

the lesser long-nosed bat co-occurs in large numbers with up to three species ofmormoopid bats,

which generally live in hot, dry roosts (Bonaccorso et al. 1992) (Table 1). In Arizona, it tends to be

the single occupant of caves or mines, although Hayward and Cockrum (1971) reported that it

sometimesroosts withMaorcaus californicus,Choeronycteris mexicana, Plecotustownsendii,Myotis

velifer, and M. thysanodes. Hoffineister (1986) has a record ofL curasoae inhabiting a mine in the

Picacho Mountains with Tadaridabrasiliensis and M. vdlifer.

Because abandoned mines are important roost sites for Leptonycteris throughout its range, it is

important to evaluate the status of mines asroosts for this bat and shelters for other wildlife before

they are permanently closed. Even closing some but not all exits from mines and caves may have

a detrimental effect to the bats. Individuals at Hilltop Mines and Copper Mountain Mine have been

shown to use more than one exit at a time in leaving the roost.

Like many otherbats, individuals ofLeptonycteris use night roosts for digesting theirmeals. These

roosts include the bats’ day roosts as well as other caves, mines, rock crevices, trees and shrubs, and

occasionally abandoned buildings (Cockrum 1991, Hoyt et al. 1994). The extent to which night

roosts represent essential habitat in this species is currently unknown.

Whatever its day-roosting location, L. curasoae appears to be sensitive to human disturbance.

Fleming’s experiences in mines near Alamos, Sonora, Mexico, and in East Whitetail Canyon (Hilltop

Mines), Arizona, indicate that a single briefvisit is sufficient to cause a high proportion oflesser

long-nosed bats to temporarily abandon theirroost and move to another. Inthe Alamos region, most

disturbed bats return to their preferred roost in a few days. Additional information is needed on the

reoccupation of sites that have been disturbed. Census information from Cave of the Bells in

southern Arizona indicates that reoccupancy ofa roost once ithas apparently been abandoned, is not

certain. Censuses on September 9-10, 1987, showed 1,500 to 2,000 bats present. The cave was
6

Table 1. Other species ofbats known to roost in the same cave or mine with Leplonycteris cura.soae

verbabuenae1

iEamilv ___

Phyllostomidae

Vespertilionidae

Mormoopidae

Phyllostomidae

Natalidae

Vespertilionidae

Molossidae

Choeronycteris mexkana

Macrotus californkus

Myotis thysanodes

Myotis velifer

Plecotus ta~sendli

Monnoops megalnphylla

Pteronoius davyi

G1oss~phaga —

Glossophaga soricina

Macrotus californicus

Macrotus waterhonsii

Leptonycteris nivalis

Natalus stramineiis

Myotis velifer

Tadarida brasiliensis

Arizona

Mexico

1Sources: Hayward and Cockrum (1971), Wilson (1985), T. Fleming (unpubl. data).
7

watched closely in 1987, 1988, and 1989 as part of a project to develop a gate design acceptable to

the bats. Information obtained showed that this cave was used for a limited time period and the bats

very quickly left in September. Census figures for September 7, 1988, were 175 bats and 170 were

present in early September 1989 when a mock-up ofthe gate was installed. The numbers of bats

using the cave decreased quickly after the mock-up was installed, but this was not seen as unusual

given the past censusinformation. The real gate was installed in the winter/spring of 1990 and the

door latched open to allow the bats free access. However, no bats were seen using the cave in 1990

and none have been seen since.

Interspecific interactions with other bat species may also influence lesser long-nosed bat roost

requirements. Although it occurs with up to four other species ofbats in certain Mexican caves or

mines (Table 1), it tends to roost separately, often deeper in the cave or mine, than other bats. Lesser

long-nosed bats do not show up in numbers at Bat Cave near Patagonia, Arizona, until after a large

maternity colony ofMyotis velifer abandons the site in late July, though whether the two species

interact negatively is not currently known.

As discussed in more detail below, food requirements ofthe lesser long-nosed bat are very specific.

Adequate numbers offlowers and/or fruit are required within foraging range ofday roosts and along

migration routes to support largenumbers ofthis bat. Locations ofgood feeding sites therefore play

an important role in determining availability of potential roosting sites, and roost/food requirements

must be consideredjointly when discussing the habitat requirements ofthis bat. A suitable day roost

is probably the most important habitat requirement, but potentially suitable roosts must be within

reasonable foraging distances ofsufficient amounts ofrequired foods before they will be used by this

bat.

Foods

The lesser long-nosed bat has specialized food requirements. Coluninar cactus flowers and fruits

and Agave flowers are believed to represent this bat’s core diet (sensu Fleming 1986). Its

consumption of nectar and pollen produced by paniculate Agave flowers is well-known (e.g. Howell

1974, 1976, 1979). Important also are nectar, pollen, and fruit produced by a variety ofcolumnar

cacti (Howell 1974, Cockrum 1991, Fleming et al. 1993). Flowers and fruits of 2-3 species of

columnar cacti (Pachycereus pringlei, Carnegia gigantea, and Stenocereusthurberi, (Table 2)provide

nearly all ofthe energy and nutrients obtained by pregnant and lactating females roosting in the

Sonoran desert in the spring and early summer.

While it is well documented that the lesser long-nosed bat utilizes Agave and columnar cactus as its

primary food resources (at least in the Sonoran Desert), there remain other questions. The range of

the primary Agave and columnar cactus species used as forage plants in Arizona extend further north

than doesthe known range ofthe bat and thus do not entirely overlap. The occupation ofroosts in

areas before or after the main blooming or fruiting period ofthe local forage plants is also a question

that needs to be examined. Proper management of forage plant species requires we understand how

the lesser long-nosed bat is using these resources. This includes developing information on
8

economical flight distances and suitable distribution offorage plants around the roost sites and along

migratory paths.

Seasonal changes in the importance of cactus and agave in the diet of Leptonycteris have been

demonstrated using stable isotope techniques. Cacti and agaves have a special photosynthetic

pathway known as Crassulacean Acid Metabolism (CAM) and hence have different stable carbon

isotope ratios than do plants using the Calvin photosynthetic pathway (C3). C3 plants provide food

for Leptonycteris south ofthe Sonoran Desert in Mexico (Alvarez and Gonzalez 1970, Quiroz et

al. 1986). Fleming, Nunez, and Sternberg (1993) reported that on the Mexican mainland, tissues of

L. curasoac contain mostly C3 carbon from October through February and mostly CAM carbon in

the spring and summer.

Northern migrants and those living on Baja California year-round were nearly exclusively CAM in

carbon composition. The southern subspecies ofL. curasoae also feeds almost exclusively on CAM

plants year-round on Curacao (Petit 1995). In addition to cacti and agaves, this bat is also known

to feed at the flowers ofat least five C3 plant species in Mexico (Table 2).

By eating nectar, pollen, and fruit, Leplonycteris bats are important pollinators and seed dispersers

oftheir food plants. The importance of L. curasoac as a pollinator ofcolumnar cacti appears to vary

geographically. In the Sonoran Desert, the results ofexclusion experiments indicate that this bat

appears to be an important pollinator ofPachycereius pringlei and Stenocereus thurberi but is less

important than white-winged doves as a pollinator of (McGregor et al. 1962,

Fleming et al. 1995). Farther south in Mexico and in Venezuela and Curacao, exclusion experiments

indicate that Leptonycteris and other species ofbats are the most important pollinators ofcacti in the

genera Neobuxbaumia, Stenocereus, Pilnsocereus, and Subpilocereus (Nassar 1991, Petit 1995,

Valiente-Banuet et al. 1995). Similar kinds of exclusion experiments are being conducted on Agave

palmeri in southern Arizona by Liz Slauson (Arizona State University). At one site, fruit set before

the seasonal arrival ofbats ranged from 1-70% in three plants compared with an average of 28% in

the same plants after the arrival of bats. Her results indicate that visits by native bees and

hummingbirds, as well as those by bats, result in fruit and seed set in this agave. Alternatively,

Howell and Roth (1981) indicate that these bats are the primary and most important pollinators of

Agave flowers. The importance ofthe lesser long-nosed bat to the pollination of agave flowers

remains a subject of dispute within the scientific community.

Only one study has addressed the importance of Leptonycteris bats as dispersers ofthe seeds of

columnar cacti. Vinicio Sosa (pers. comm.) conducted exclusion experiments at Bahia Kino,

Sonora, Mexico, in which ripe fruits were available only to nocturnal, only to diurnal frugivores, or

to both nocturnal and diurnal frugivores, in P. pringlei, C. gigantea, and S. thurberi. His results

indicate that seed removal by bats was much lower than removal by birds at this site.

Because it is a major pollinator (and potential seed disperser in the case of columnar cacti) of

columnar cacti and paniculate agaves, both of which are highly distinctive elements ofthe flora of

Mexico and the southwestern United States, L. curasoae can be viewed as a “keystone mutualist” in
9

Table 2. Major food plants ofLeptonycteris curasoae yerhahuenae’

Family ~rI~0p1 ~ Fond Tvne ~~..mdA,LJ.LlI.L ~,P’-•’-.’-.<. —_________________________________ 2

Agavaceae

Cactaceae

Agavaceae

Cactaceae

Agave—Agave parryi

Agave deserti

Carnegia gigantea

Stenceereus thurberi

many Agave species

Carnegia gigantea

Stenocereus spp.

Pachycereus spp.

Ne~buxbaumia spp.

and other columnar

spp.

Bombax ellipficnm

Ceiba spp.

Ipomea arborescens

Bauhinia ungulata

Crescenfia alata

Bombacaceae

Convolvulaceac

Leguminosae

Bignoniaceae

N,P

N,P

N,P

N,P,F

N,P,F

N,P

N,P,F

N,P,F

N,P,F

N,P

N,P

N,P

N,P

‘Sources: Alvarez and Gonzalez (1970), Hayward and Cockrum (1971), Howell and Roth

(1981), Quiroz et al. (1986), Valiente-Banuet et al. (1995), T. Fleming (unpubl. data).

T

Arizona

Mexico

= Nectar, P = Pollen, F = Fruit
10

the sense that its impact on arid habitats is larger than would be expected solely from its abundance.

Its migratory behavior also makes it an important “mobile link” between geographically separated

habitats (e.g., desert lowlands and Sierra Madre uplands, tropical dry

forest and Sonoran Desert). Therefore, its protection is important for the reproductive success of

some ofthe dominant plants in a variety ofarid and semiarid habitats in North America.

Population Ecology

Many aspects ofthe population ecology ofthe lesser long-nosed bat are poorly known. Hayward

and Cockrum (1971) remains the main source ofinformation about the population ecology ofthis

species. It is not yet known whether adult females produce one or two young, in one or two

pregnancies, per year (Wilson 1979). Current information suggests that most females bear only a

single young per year and that timing of mating and parturition varies geographically. Females in

southern Guerrero and Chiapas (1 6o~ 170N) give birth in December; those in the Cape region ofBaja

California Sur(230 N) in March; and those in Sonora and southern Arizona (2R N and above) during

May (Quiroz et al. 1986, Cockrum 1991, R. Medellin, pers. comm., V. Dalton, pers comm., T.

Fleming, unpubl. data). It is likely that periods ofbirth and lactation coincide with peak flower

availability (cactus flowers in the case ofBaja and Sonoran/Arizona bats; C3 plants in the case of

bats in southern Mexico). If gestation length is four months, as is the case in many species of

phyllostomid bats (Fleming 1988), conceptions likely occur in August, November, and January,

respectively. Females ofL. c. curasoac on Curacao and in Venezuela give birth to one young per

year; birth occurs in May (Petit 1995, A. Arends, pers. comm.).

Parturition is not highly synchronous in maternity roosts ofthe lesser long-nosed bat. Femalesin

different stages ofpregnancy and young ranging in age from newborns to nearly volant juveniles

have been found atthe same time in maternity roosts (e.g. Colossal Cave and Copper Mountain mine

in Arizona, Sierra Kino Cave in Sonora, Cueva “La Capilla” in Baja California Sur) (Hayward and

Cockrum 1971; Y. Petryszyn, pers. comm.; T. Fleming, unpubl. data). This asynchrony suggests

that females conceive at slightly different times, possibly in different roosts, before occupying

maternity roosts.

Females give birth to a single pup weighing about 30% ofits mother’s weight. Sex ratio at birth

appears to be close to 1:1 (Hayward and Cockrum 1971). Young Leptonycteris have well-developed

feet and are left to hang in the day roost from the day ofbirth while the mother leavesthe roost to

forage. Young probably are nursed for about six weeks, begin to fly at four weeks, and begin

leaving the roost on evening flights at six to seven weeks.

Locations ofknown maternity roosts are shown in Figs. 1 and 2. These roosts occur throughout the

range ofthe lesser long-nosed bat. Many female L. curasoae appear philopatric to a particularroost,

both maternity and other. Hayward and Cockrum (1971) reported recapturing many females in

Colossal Cave that had been banded there 2-3 years earlier. Similarly, on 3 May 1972, P. Brown

(pers. comm.) recaptured two adult females in the Bluebird Mine that she had banded there on 16

September 1971.
11

Roost sites, sex ratios, and seasonal changes in roost size have been documented at relatively few

locations. L. curasoae is unusual among phyllostomid bats because it often roosts in very large

colonies that may contain thousands to tens ofthousands ofindividuals during both the maternity

and non-maternity periods (Arita 1993). Most phyllostomids roost in colonies containing less than

1,000 individuals (Fleming 1993). Estimates ofthe sizes ofroosts visited by Fleming and others in

1992-93 are summarized in Table 3. These roosts contained from 1,000 to over 100,000

Leptonycteris bats. The largest currently known colony ofthis bat is a maternity roost that likely

contains over 100,000 adults located in Pinacate Biosphere Reserve, Sonora, Mexico. A sea cave

in Chamela Bay, Jalisco, Mexico, contained over 50,000 L. curasoac in October 1992. Not all

members ofthis species, however, roost in large colonies. For example, Fleming noted a group of

six Leptonycieris roosting in a small cave near Ocotlan, Jalisco, Mexico, in October 1992, and

Sidner and Davis (1988) reportedgroups of 15-50 females at several locations in southern Arizona

in 1986 and 1987. Cockrum and Petryzsyn (1991) report other occurrences ofsmall numbers of

Leptonycteris in Arizona and elsewhere.

Assessment ofpopulation trends in the lesser long-nosed bat, requires accurate census techniques.

Highly gregarious bats, such as L. curasuac, which roosts with other gregarious bats (e.g. species of

Mormoopidae), are difficult to census. Two different techniques were used to obtain the data in

Table 3, exit counts and visual censuses within day roosts. Dalton and Dalton (1993) are

investigating the use ofinfrared light and video cameras to film bats exiting the roosts. Counts can

- ~ then be made later. At certain roosts (e.g. Copper Mountain Mine, Pinacate Cave), reasonably

accurate exit counts are feasible because L. curasoae is the sole inhabitant, bats fly straight out of

the roost without excessive “swirling around” at the entrance orreturn flights, and they depart at

rates slow enough for accurate counting. In May 1992, Fleming and Yar Petryszyn simultaneously

countedbats exiting from those two roosts and obtained numbers that were within 5% of each other.

Such exit counts are likely to underestimate the total number of bats in a roost because not all

individuals leave with the first wave ofdepartures. Counts of bats exiting roosts can also be used

as an index of population size over time if the same techniques are used and it is assumed the

percentage ofthe population leaving the roost is similar for the same time ofyear. Alternatively,

Howell, in comments on this report, states “swirling” at the entrance to the roost before leaving is

a normal behavior in this species. She also questioned the correctness ofcensus counts obtained by

exit counts. The issue of“swirling” remains to be addressed.

The second and most commonly used censustechnique is to quietly enter a roost during the day to

obtain a visual count ofthe resting bats. When using this technique, Petryszyn and Fleming attempt

to quickly note the areal coverage ofLeptonycteris bats in square feet (ft2) before many bats take

flight and then multiply that numberby an estimate ofthe number ofbats per ft2. The density of bats

will vary by roost, season, temperature and other factors. Petryszyn usually uses an estimate of 50

bats per ft2. This is a conservative value because Leptonycteris bats are contact-loving and often

roost by day in very dense masses ofconsiderably more than 50 per ft2. Depending on the density

of bats, Fleming used values of 50 or 100 bats per ft2 in his calculations. With both census

techniques, Petryszyn and Fleming have tried to be conservative in estimating the size of

Leptonyctens roosts.
12

Table 3. Estimated sizes ofroosts of Leptonycteris curasoae yerbabuena~ in Arizona and Mexico in 1992-93.

______________________ ______ __________________ Location ~Datc

Observers Estimation Number

ARIZONA

Bluebird Mine

(Cabeza Prieta NWR)

Copper Mountain

Mine (Organ Pipe

Cactus NM)

Copper Mm.

Copper Mm.

Copper Mm.

Old Mammon Mine

(near Casa Grande)

Old Mammon Mine

Hilltop Mines

(Chiricahua

Mountains)c

Patagonia Bat Cave

(Coronado NF)C

Patagonia Bat Cave

Patagonia Bat Cave

Patagonia Bat Cave

5/14/92

5/01/92

5/15/93

7/16/93

08/07/93

06/21/92

5/29/93

5/15-16/93

08/29/92

08/13/94

08/25/94

09/14/94

TF, DD vC

YP EC

YP

VD,DD

VD,DD

EC

IR

IR

VD BC

VD BC

TF VC

TF,YO VC

DN

DN

TD

EC

EC

ca. 3000

10,400 adults

20,000 adults

17,909

15,166

3,600 adults

and young

ca. 3,600

200-400

adults

19,800 adults

and young

55,000-58,000

38,000

3,400

Manila Mine (Fort

(Huachuca)c

Manila Mine

State ofTexas

Mine (Coronado NMC)

State of Texas Mine

State of Texas Mine

Box Canyon Crevice

(Saguaro NM)C

Box Canyon Crevice

MEXICO

Sierra Kino Cave

near Bahia Kino,

Sonora

RS

SS

DN

20-45

1,400

BC

Aug-Sep 91

10/14/93

08/25/93

08/13/94

08/25/94

05/12/67

May-July 91

springs

1989-95

DN

DN

BC

BC

RS

TF

ca. 20,000

12,550

14,000

21

1F

1-2

up to 2,600

adults

BC

(continued)
13

Table 3. (Continued)

I Ar2tinl, fl,1tF.

Bstimation Number

L. ‘“ iroc tXoo

Pinacate Cave, Sonora

Pinacate Cave

San Domingo Mine,

Alamos, Sonora

San Domingo Mine

San Domingo Mine

Cueva del Tigre

near Carbo, Sonora

Cueva “La Capilla”

near Buenavista,

Baja, Calif. del Sur

Gruta Juxtlahuaca,

Colotlipa, Guerrero

Isla San Andres

Cave, Chamela, Jalisco

Cueva “La Mina”

Ajiijic, Jalisco

05/16/92

05/16/93

10/20/92

02/13/93

04/30/93

05/02/92

04/12/93

11/14/92

10/29/92

11/02/92

TF,YP,DD

YP

TF

TF

TF

TF

BC

BC

VC

VC

VC

VC

TF VC

TF VC

TF VC

TF BC

>80,000 adults

ca. 130,000 adults

ca. 1,000 adults

adults

ca. 20,000

aduits

>20,000 adults

ca. 1,000 adults

ca. 20,000

adults & young

ca. 2,000 adults

>50,000 adults

>20,000 adults

aDD = David Dalton, TF = Ted Fleming, VD = Virginia Dalton, YP = Yar Petryszyn, DN = Debbie

Noel, SS = Sheridan Stone, RS = Ronnie Sidner

bEC = Exit count, VC Visual census, IR = Infrared video, -- = no method listed.

clndicates a transitory roost. Bats found in these roosts July may include adults and young from known

maternity roosts. Adult males may use these during the early summer.

dAdults from this roost move to Isla Tiburon Cave to give birth.

eNumbers increased to 150,000 adults and young by August 1992.

~Thesefigures were from the same year as the Colossal Cave maternity roost likely was abandoned due

to the installation ofthe fan. The decline in numbers from 1967 to the present may represent the

unsuitability ofthis cave to be a maternity roost, although females are still found there in low numbers.

Note: Total population size ofthe lesser long-nosed bat cannot be obtained by adding the numbers in

this table.

Observer3
14

Adult sex ratios in roosts ofthis bat vary geographically. With the important exception of at least one

cave (Buckalew prior to 1969) and one mine (Hilltop recently) in the Chiricahua Mountains of

Arizona, roosts in Sonora and the United States contain over 95% adult females. Some ofthe

population figures presented in this table for roosts in Arizona and northern Sonora are disputed by

other researchers familiar with this species. Short- and long-term monitoring ofthese populations

using standardized methods will be needed to resolve these differences.

The Chiricahua male roosts have contained 300 to 1,000 males. From Jalisco, Mexico, south,

Lepitonycteris rooststend to be male-biased. For example, more males than females were captured

at 24 of 36 sites (67%) from Jalisco south whereas 7 of9 sites (73%) north ofJalisco were femalebiased in the mammal collection ofthe Instituto de Biologia, Universidad Nacional Autonoma de

Mexico (T. Fleming, unpubl. data). The concentration of males in the southern half of Mexico

suggests that most females mate in the south before migrating north each spring (Wilson 1979). As

suggested by Cockrum and Ordway (1959), it is also likely that some northern females that did not

give birth in the spring mate with malesroosting in southeastern Arizona (and perhaps southwestern

New Mexico) in the late summer or early fall before migrating south. Ifthis is true, then caves and

mines in the Chiricahun and Animas Mountains represent important mating sites for this species and

must be protected from human disturbance. Roosts undoubtedly fluctuate in size and composition

during the year. This is obviously true for the northern maternity roosts. Observations at the

maternity roosts in Organ Pipe CactusNational Monument and Pinacate Biosphere Reserve indicate

that they are occupied from mid-April to early-to-mid-September (pers. comms. from V. Dalton, W.

Pechey, and Y. Petryszyn). The maternity roost in Cueva del Tigre is occupied from early April

until early October. Bat Cave near Patagonia is occupied from mid-July to early September. The

maternity roost near Alamos, Mexico, probably contains some bats year-round (e.g. Table 3), but

numbers increase to tens of thousands when female migrants return in January or February.

Numerical changes in the Chamela Bay roost were monitored monthly from March 1993 through

February 1994, and a large decrease in numbers occurred in April and May 1993 (G. Ceballos, pers.

comm.). This decrease may be the result offemales migrating north.

Longevity and sources ofmortality have not been studied in L. curasoae. Hayward and Cockrum

(1971) reported recaptures ofbats four(n=2), six (n=1), and eight (n=l) years after banding. The

latter two females were at least seven and nine years old, respectively, at the time ofrecapture. If

they survive their first few months oflife, many bats, including tropical phyllostomid bats, can live

for as long as 10 years (Tuttle and Stevenson 1982, Fleming 1988). It is likely that longevity in L.

curasoae is similar. Major bat predators include snakes in roosts, camivores at roost entrances, and

owls while the bats are foraging. On Isla Margarita offthe coast ofVenezuela, bam owls feed on

Leptonycteris bats (K. Silvius, pers. comm.). Unlike many other phyllostomid bats, however, L.

curasoae is not lunar-phobic (i.e. it does not reduce its foraging activity during the bright time ofthe

lunar month), which suggeststhat it does not suffer strong selection pressure from nocturnal aerial

predators (M. Horner and T. Fleming, unpubl. data).

The mating system ofthe lesser long-nosed bat is currently unknown. Many phyllostomid bats have

harem-polygynous mating systems in which a small number of adult males defend and mate with
15

groups ofsexually receptive females (Fleming 1988). Whether this is true for nectar-feeding bats

requires further study. Males and females spend considerable portions ofthe year separated from

each other; however, this does not preclude the formation ofharems during the breeding season.

This information is important because the form ofthe mating system will determine genetically

effective population sizes, levels of genetic diversity in populations, and the degree to which

disturbances of male roosts affect the reproductive success ofthis species.

Current information indicates that L. curasoae in Mexico has a large genetically effective population

size (Wilkinson and Fleming 1995). mtDNA haplotype diversity is high, and the Mexican

subspecies contains two matrilineal clades displaying a 3% divergence in gene sequences in the

mitochondrial control region. Members of these clades co-occur in the same roosts throughout

western and southern Mexico. A divergence value of 3% is unusually high in mobile vertebrates

(Avise 1989) and suggests that gene flow is extensive in this species. Contrary to the situation in

a variety ofspecies ofNorthAmerican vertebrates (Avise 1989), there is no evidence indicating that

Leptonycteris has recently undergone a demographic bottleneck that has reduced its genetic

diversity.

An extremely important feature ofthe population ecology of the lesser long-nosed bat is its mobility.

Many individuals undertake long seasonal migrations and fly long distancesfrom their day roosts

to forage each night. This nightly mobility was first discovered during a radiotracking study of L.

curasoae at Bahia Kino, Sonora, Mexico, in 1989 and 1990 (Sahley et al. 1993 and unpubl. data).

Bars feeding on the Mexican mainland roosted during the day on Isla Tiburon, 25-30 kms away.

Tracking data indicate these bats fly for about 6 hours each night for a total flight distance of 80-100

kms. Flight speeds while commuting between day roost and feeding areas averaged 30-40 km per

hour and averaged 16 km per hour while foraging. The cost of commuting from Isla Tiburon to the

mainland was calculated to equal about 7-8 flower visits. Since bats visit over 100 Pachycereus

pringici flowers per night (Sahley et al. 1993 and unpubl. data), these relatively long commute flights

require comparatively small amounts of energy. Density of forage plants may be an important factor

in determining optimal or acceptable foraging distances.

Howell (1994) radiotagged 24 Leptonyciteris roosting in the Blue Bird mine in southwestern Arizona.

Adult bats tagged in early July 1993, when cactus flower and fruit densities were relatively high,

commuted an average of 8.6 miles (13.8 km) to their feeding areas; juveniles commuted an average

of 4.7 miles (7.5 kin). In late August, when cactus food resources were scarce, adults commuted

10.9 miles (17.5 km) from the roost to feed. In both tracking sessions, several radiotagged bats flew

from the Blue Bird mine to the Copper Mountain mine, a distance of about 15 miles (24.2 km), to

feed and roost.

Efficient flight profoundly influences the roosting strategy ofthis bat. Because they can fly long

distances at low energy costs, the lesser long-nosed bat can afford to roost long distances from good

feeding areas. Bats roosting in the Pinacate Cave provide an excellent example. Most ofthe area

around this cave, which seasonally houses over 100,000 adult females and their young, is devoid of

cactus and agave plants. The closest substantial densities of cactus flowers and fruits are found in
16

Organ Pipe Cactus National Monument, about 40-50 kms away. It is likely that a substantial

proportion ofthe Pinacate bat population, including newly weaned young, commute 40-50 kms oneway each night to feed.

A second example comes from male bats roosting in the ChiricahuaMountains in May. Preliminary

analysis offresh fecal material collected on May 15, 1993, revealed the presence oflarge amounts

of cactus pollen (probably saguaro, Carnegia gigantea) and small amounts of Agave pollen. There

are no flowering columnar cacti and some flowering agaves in the Chiricahuas in May. The closest

locations of saguaros, either Saguaro National Monument East or north of Safford, are 125 kms

away. While the actual flight distances of these bats require careful study, these and other

observations suggest that the foraging radius ofLeptonyctens roosts may be on the order of 50-100

kms. Iftrue, large roosts ofthis bat could forage over an area of 7,855-31,416 km2, depending on

the density and location of suitable food plants. From these calculations it seems evident that

Leptonycteris bats forage over wide areas and that large roostsrequire extensive stands of cacti or

agaves for food. Therefore, destruction offood plants many kilometers from Leptonyciteris roosts

could have a negative impact on this bat.

Present Status

The lesser long-nosed bat is apparently far more common in Arizona than the 500 found by D. E.

Wilson at the Patagonia Bat Cave on July 16, 1985. In his Leptonycteris survey, Wilson did not visit

Hilltop Mines in the Chiricahuas and Copper Mountain Mine at Organ Pipe Cactus National

Monument. He visited Old Mamnion (on the morning of July 19, 1985) and Bluebird (in the

afternoon ofJuly 19). He noted the presenceof bats in inaccessible vertical shafts at Old Mammon

but did not stay long enough to net them on their evening exit. At Bluebird, he noted the presence

of lots of “red droppings” (= fruit pulp from saguaro or organ pipe cacti?) on the mine floor but

found no Leptonycteris bats. Wilson (1985) reported that nectar-feeding bats heavily visited

hummingbird feeders near Portal in the Chiricahuas and at Ramsey and Madera Canyons in the

Huachuca and Santa Rita Mountains, respectively, and suggested that L. cura.soae might be more

common in southeastern Arizona than indicated by his survey. Current evidence indicates that his

suggestion is correct.

Results ofsome recent census and survey efforts indicate thousands oflesser long-nosed bats roost

and/or feed in Arizona seasonally; however, as discussed earlier, this is disputed by some members

ofthe scientific community. This discussion assumes that the higher figures are more representative

ofthe bat population at present. Prior to mid-July, most ofthe bats known to be roosting in Arizona

are concentrated in three main maternity roosts southwest of Tucson (Fig. 2). Ofthese, the Copper

Mountain roost is the largest and contains nearly 20,000 adult females that give birth to somewhat

less than this number of young. The Bluebird and Old Mammon mines contain up to 4,000 adult

females. Before they give birth, bats probably occasionally move between Copper Mountain and

Bluebird Mines. It is important to censusthese two roosts simultaneously to avoid double-counting

bats. It is likely that a significant portion ofthe bats from the Pinacate Cave enter southwestern

Arizona each night to feed. Including only those bats in Arizona roosts, the lesser long-nosed bat
17

population in early summer is estimated to be at least 80,000 adults and newly volant young. It is

recognized that many young bats do not survive their first year.

Beginning in mid-July, bats startto roost in large numbers at two locations in south-central Arizona

-- Patagonia Bat Cave and the State ofTexas Mine (a new colony discovered in 1993) -- and feed

on Agave flowers. Numbers at the Patagonia Bat Cave increase from a few hundred in late July (as

noted by Wilson) to 20,000 in late August (Table 3), likely from the arrival of bats from the

maternity roosts. Simultaneous exit counts at this cave and at the State of Texas Mine on August

13, 1994, revealed about 56,000 and 12,000 bats, respectively (D. Noel and Y. Petryszyn, pers.

comm.). Numbers oflesser long-nosed bats also increase in the Hilltop Mine asfemales and young

join the adult males residing there from May on; by early September in some years, that roost may

contain as many as 3,000-4,000 bats (Cockrum and Petryszyn 1991; R. Taylor and M. Tuttle, pers.

comm.). Coincident with the movements offemales and young into southeastern Arizona, people

in the Portal area report significant increasesin bat visits to their hummingbird feeders (S. Schmidt,

pers. comm.). Most bats have left these post-maternity or transitory roosts by mid-September, but

some bats remain to visit hummingbird feeders into October. A similar pattern of temporary

residence from mid-July until early September by both species of Leptonycterislias occurred in

recent years in the Animas Mountains ofsouthwestern New Mexico (Hoyt et al. 1994).

As mentioned earlier, genetic evidence (Wilkinson and Fleming 1995) indicates that bats roosting

in south-central and southeastern Arizona are not the same bats asthose roosting in southwestern

Arizona. Eastern bats apparently inhabit different winter roosts than western bats and follow a

different migratory route along the Sierra Madre mountains into Arizona in the summer.

Fleming’s research in Sonora in the springs of 1989-93 and his travels in mainland Mexico and Baja

California in the fall of 1992 and spring of 1993, respectively, also indicate that the lesser long-nosed

bat is far more common in Mexico than Wilson (1985) found in his surveys of Leptonycteris

localities during the summerof 1983 and spring of 1984. Inthe spring in Sonora, maternity colonies

occur in Santo Domingo Mine near Alamos, Cueva del Tigre near Carbo, on Isla Tiburon, and in

Pinacate Cave (Table 3). Anothermaternity colony near Tajitos, Sonora, was reported by Hayward

and Cockrum (1971), but its currentstatus is unknown. In the fall of 1992, non-maternity colonies

of lesser long-nosed bats were located near Alamos, Sonora; Chamela Bay, Jalisco: Ajiijic, Jalisco;

and Gruta Juxtlahuaca, Guerrero (Table 3). In the spring of 1993, a large maternity colony was

located near Buenavista, Baja California Sur (Table 3). In addition, numerous bats ofthis species

were commonly seen in large stands of cardon cactus at several locations farther north in Baja Sur.

Based on museum collections, at least two other maternity roosts are likely to exist in Baja

California Sur -- a mine near San Antonio and a cave near Mulege. The status ofthese roosts needs

to be ascertained. In January 1993, Rodrigo Medellin visited a lesser long-nosed bat cave near

Tuxtla Guttierez, Chiapas, that has contained thousands of bats in recent years; he reported finding

10,000 females and theirrecent young.

Many areas likely to harbor significant numbers of lesser long-nosed bats (e.g. in Sinaloa and

Guerrero) cannot be safely visited by biologists because ofillegal drug activities. Hence, a complete
18

survey ofLeptonycteris sites in Mexico is presently not possible. Even with incomplete information,

however, it is possible that the lesser long-nosed bat population in Mexico currently numbers in the

hundreds ofthousands.

There are two principal reasons for the discrepancy between Wilson’s estimates of the size of

Leptonyctens populations and current estimates. The first is that Wilson did not visit many ofthe

caves or mines harboring significant populations of Leptonycteris in Arizona and Mexico. Second,

Wilson may have visited some caves or mines at the wrong time ofthe year. This certainly is true

in the case ofthe Patagonia Bat Cave in Arizona. Wilson visited the cave while it was still full of

Myotis velifer and before the bulk ofthe Leptonycteris had arrived. Not finding Leptonycteris bats

in Bluebird Mine is not unusual as other bat biologists (e.g. V. Dalton) have failed to find this

species there on occasions in May and June. To an extent that is not yet fully documented, some

roost populations oflesser long-nosed bats appear to be very fluid, and some bats probably undergo

frequent shifts in roost occupancy (e.g., between the Blue Bird and Copper Mountain Mines) within

and between seasons as Fleming and his students have observed in the Bahia Kino region ofSonora.

Until the factors affecting these shifts (e.g. changes in local resource densities, social activities) are

better understood, it will be difficultto accurately estimatetotal population sizes ofthis bat. Because

ofthis mobility, the timing ofcensus surveys is critical, particularly those involving one-day visits;

negative results (i.e. no bats seen) must be interpreted cautiously. This may be an explanation for

some of Wilson’s results. Likewise, care must be taken not to double-count bats moving from one

roost to another.

Surveys and censuses in 1973, 1976, 1977, and 1985 by Howell, Wilson, and other biologists

indicated that significant declines had occurred in the lesser long-nosed bat populations at least in

southern Arizona. Reasonsfor this reported decline have been suggested, but hard evidence ofthe

cause and effect relationship, if any, is scant because ofthe difficulty in dealing with a wide-spread

migratory species. Howell and Roth (1981) and Wilson (1985) cited general habitat destruction and

overharvesting of Agave plants for the manufacture of mescal as possible contributing factors. The

popular press (e.g. Heacox 1989) has publicized the idea of a “fatal attraction” between

Leptonycteris bats and Agave plants, but recent work by Gary Nabhan (Nabhan and Fleming 1993)

indicates that “there are very few places in Sonora or anywhere else in Mexico where wild Agave

harvesting has eliminated a significant percentage ofnectar-producing genets [clones].” Even in the

few areas that do show overharvest, there are agaves remaining in steeper or otherwise inaccessible

terrain that are available to the bats. Nabhan has suggested (pers. comm.) that vegetative, rather

than sexual, propagation of agaves occurs in areas of heavy harvesting. The flowering stalk is

removed but the offshoots ofthe same plant remain and flowering may be delayed but the eventual

opportunity is not eliminated. The harvest of approximately two million agave heads per year for

mescal production in Sonora has resulted in a reduction of agave nectar and pollen resources over

300 miles ofthe migratory pathways, but the extent to which this reduction has a significant effect

on the bats, given their ability to forage over long distances, requires additional evaluation. It is

clear that population pressures and continued human use ofthe desert lands has had an effect on the

columnar cacti and agave, and that each year additional acreage is lost in Arizona, New Mexico, and

Mexico and the long-term effects ofthese losses is not known.
19

An interesting connection between human agricultural activities is the possible importance ofthe

millions of Agave mu.rphei planted by the Hohokam and other groups of native people from

Magdalena and Caborca in Mexico to the Tonto Basin in Arizona to migrating lesser long-nosed

bats. This agave species was cultivated and its spread by native peoples provided a food resource

for the bats that may have provided them with resources at a time when other agaves and columnar

cactus are not blooming. A. murphei is a reliable, March-April bloomer and its presence may have

facilitated the migrations to Arizona. Populations of A. mnrphei have significantly declined in the

last 400 years since they are no longer actively cultivated. We do not know what effect this decline

has had on the success of migrations during the early part ofthe season.

Roost disturbances inMexico would seem to be an obvious source ofmortality for lesser long-nosed

and otherbats, but Wilson (1985) found no overt evidence ofdisturbance in the caves he visited that

lacked Leptonycteris bats, although this does not preclude human entrance to the caves that left no

real trace. Fleming has seen photographs ofthe destruction by fire ofthese bats in the Sierra Kino

Cave near Bahia Kino, Sonora, yet the bats continue to roost there. Two large Leptonycteris roosts,

Santo Domingo Mine and Cueva “La Mina” (Table 3), are located within a few hundred meters of

towns and are well-known by local residents, who seemingly ignore the bats. Recent information

on the effect of military aircraft overflights ofthe Copper Mountain maternity roost has not found

major effects to roosting bats (Dalton and Dalton 1993). Thus, proximity to humans does not

necessarily pose a threat to Leptonyciteris bats, though such locations makes these roosts very

vulnerable to any serious disturbance. Finally, Cockrum and Petryszyn (1991)summarize long-term

data on certain Mexican roosts (e.g. Cueva El Tigre and Santo Domingo mine) that have contained

Leptonycteris bats for decades. Itis important to remember that the lesser long-nosed bat is sensitive

to disturbancesin the roost, and we do not have a threshold level ofeffect that is tolerable and what

is not. That there are so fewmajorroosts known only increasesthe importance of not losing even

one roost to human disturbance. Protection ofroost sites can only go so far, and changes in local

human populations attitude toward bats is not predictable and thus remains a concern.

Reasons for Listing

Shull (1988) discussed five reasons for listing the lesser long-nosed bat as an endangered species:

(1) a long-term decline in its populations; (2) recent reports ofits absence from previously occupied

sites; (3) a decline in the pollination ofcertain agaves; (4) the results of Wilson’s status survey; and

(5) concern for death ofan ecosystem. Cockrum and Petryszyn (1991) discuss in detail why they

believe that this listing is unwarranted. Their reasoning has been challenged by Howell (1991) and

this is one of the issues that remains under dispute. An analysis of the currently available data

provides an opportunity to review these arguments.

1. and 2. Long-term population declines and absence of the species -- Except for the

deliberate elimination ofthe Colossal Cave maternity roost by humans and the lack of occupation

in Buckalew Cave since the late 1960’s, well-documented evidence that populations ofL. curasoae

have declined in Arizona or elsewhere in recent decadesis very limited. Howell and Roth (1981)

report that, except for 135-200 Leptonycteris in the Patagonia Bat Cave, they did not find this
20

species in surveys of caves and mines conducted in 1974, 1976, and 1977. Unfortunately, their

report is not detailed enough (i.e. it lacks dates and localities) to document a finding for or against

population declines. Easterla’s (1972) observations on the status of Leptonyciteris nivalis in Texas

may or may not relate to L. curasoae populations in Arizona. Evidence summarized by R. Medellin

(U.S. Fish and Wildlife Service 1994) is more convincing that populations of L. nivalis have

seriously declined in Mexico in recent decades. It could well be that populations ofLeptonycteris

curasoae and other bats have also declined in this century in Mexico. Such declines have been

documented forthe Mexican freetail bat, Tadaridabirasiliensis(Tuttle 1994). Becauseofthe absence

ofsystematic population censuses, however, these declines havenot been well-documented for most

bat species. The current difference in professional opinion on the population sizes at known roosts

complicates the evaluation of both past and present status ofthis species.

There is evidence to suggest that at least one Leptonycterisroost in Arizona, the Copper Mountain

Mine, has increased in size in the last two decades while four others have held relatively stable

numbers. Brown (pers. comm.) visited Copper Mountain several times in the early 1970s while it

was still an active mine. She noted the presence of several hundred Leptonycteris there on

September 16, 1971; 55 on May 3, 1972; and about 300 on June 5, 1972. She did not see the 10,000

or more Leptonyctens that have been reported in some surveys to occupy that roost in recent years

since mining activities have ceased. It is not known if this increase is the result of successful

reproduction or ifthese bats have moved into the mine from anothersite. There are no known roosts

in the vicinity that have been abandoned. Brown also noted nearly 400 Leptonyciteris in Bluebird

Mine in September 1971 and about 1,000 there in September 1972. These numbers are notmarkedly

different from present numbers. Neither Petryszyn nor Cecil Schwalbe (pers. comm.) have noted

declines in the numbers of Lepbonycteris bats roosting in Cueva del Tigre nearCarbo or in the Santo

Domingo mine near Alamos in the years theyhave been visiting those sites. Finally, numbers in the

Sierra Kino Cave near Bahia Kino have been steady in April during the period 1989-1995 (T.

Fleming, unpubl. data).

3. Decline in the pollination of agaves -- Howell and Roth (1981) reported a decline in the

seed set in Agave palmeri, A. deserti, and A. parryi from the late 1930s into the mid-1970s that

reportedly paralleled a decline in populations of Leptonycteris bats. The historical data on Agave

seed set apparently came from specimens housed in the University ofArizona herbarium, although

Howell (1991) hinted that the specimens came from the Desert Ecology Laboratory plant collection.

Cockrum (in Cockrum and Petryszyn 1991) reexamined available herbarium specimens at the

University ofArizona and reported that his observations did not agree with those ofHowell and Roth

(1981). The decline, or lack thereof, of Agave seed set as a consequence of changes in the bat

population is another ofthe areas where scientists familiar with the lesser long-nosed bat disagree.

There are many legitimate reasons for the different interpretation ofthe available data from the

herbarium records. In addition to an apparent confusion about the location ofthe records used by

researchers, there is disagreement about the statistical validity of using multiple seed capsules from

an individual plant. There are also external factors to consider. Specimens from different years, or

different areas may have different exposure to bat pollinators because of changes in roost occupancy

that have not been documented. This plan has already addressed the sensitivity of bats to roost
21

disturbances. Bats may or may not have been in that area at the specific time the flowers on that

specimen ofAgave was blooming. We do not know if there were many specimens blooming that

year, so the use ofany individual Agave by bats may have been higher or lower, with a resultant

difference in percent pollination. We may not know ifthe specimen was part ofa large clump that

was more likely to be found by foraging bats or if it was more isolated. The present information

does not appear to be sufficient to determine ifthere has been or has not been a bat-related decline

in seed set and the available evidence needs to be looked at more closely and additional information

collected as necessary.

4. Wilson’s U.S. Fish and Wildlife survey -- As discussed previously, there are several points

about this survey that raise questions about its completeness in documenting population sizes of L.

curasoae in Arizona and Mexico in 1983-85. The Service is required to use the best available

scientific and commercial information in making a decision to list a species as threatened or

endangered. The status report by Dr. Wilson was the best available report ofthe status ofthe lesser

long-nosed bat at that time. Wilson’s report of 15,016 lesser long-nosed bats in Mexico and 500 in

Arizona in 1985 is smaller by two orders ofmagnitude than the higher numbers reported by some

researchers in 1992-1993 (Table 3). It must also be noted, as discussed previously, that there is

disagreement about these higher population figures with some biologists believing the actual

numbers are much lower. Regardless ofwhich figures are correct, there are still only a few roosts

known forthis species and the vulnerability to extinction should one or more ofthese be lost is quite

substantial.

5. Death of an ecosystem -- Fears that the Sonoran Desert will suffer irreparable harm as a

result of declines in the size ofpopulations ofL. curasoae are speculative. While it is true that this

bat is an important pollinator and disperser of columnar cacti and pollinator ofpaniculate agaves,

other animals, including flower-visiting birds and bees in the case of columnar cacti, are also

legitimate and effective pollinators at some level (McGregor et al. 1962, Fleming et al. 1995).

Numerous other mammals and birds are legitimate cactusseed dispersers. Animals other than bats

are also effective pollinators ofpaniculate agaves (L. Slauson, pers. comm.). The greater range of

the columnar cactus and paniculate agaves in Arizona than what is known for the lesser long-nosed

bats also raises questions. Are plant populations where there are bats as pollinators more adapted

to bats than those where the bat has not been found? In addition, there have been many human

related impacts to the desert ecosystem which may play a significant role in the future distribution

ofthese forage plant species. Grazing, road construction, urban development, introduction ofnonnative plant species and collecting are all factors affecting these species. Disappearance of

Leptonycteris bats from the Sonoran Desert would likely result in reduced fruit and seed set in

columnar cacti and paniculate agaves, but the demographic consequences ofthis reduction to

populations ofplants and animals cannot be determined without further study. What can be said at

this point is that viable populations offorage species throughout the range ofthe lesser long-nosed

bat must be maintained over the long term ifthe bat is to survive.

Conservation Measures
22

Leptonycteris curasoae currently has Federal protection as an Endangered Species, and its status in

Arizona is State Endangered on the list of Threatened Native Wildlife in Arizona, 1988. Federal

agencies are mandated by law to protect these bats and consider all potential impacts on its biology

in land management practices through consultation under section 7 ofthe Endangered Species Act.

Protection and management ofits habitat requirements, including caves, mines, foodplants, etc., are

included in management plans ofthe appropriate National Park Service Monuments, U.S. Fish and

Wildlife Service National Wildlife Refuges in Arizona, and lands managed by the Bureau of Land

Management and the U.S. Forest Service. In addition, as a listed endangered animal, the lesser longnosed bat is protected against taking under section 9 ofthe Act. Take is defined as to “...harass,

harm, pursue, hunt, shoot, wound, kill, trap, capture or collect, or attempt to engage in any such

conduct...” and permits must be obtained from the Service for all research on the species that could

result in take. The Arizona Game and Fish Department maintains a database on the biology and

distribution ofL. curasoae. This database is available for use by other State and Federal agencies

in preparing impact statements and management plans.

L. curasoae is one of 13 species of mammals listed (as threatened) in Mexico’s embryonic

Endangered Species act of 1991. While no active protection is currently being provided for Mexican

endangered species, this listing is taken seriously when decisions are made regarding: the issuing

of scientific research permits to Mexican nationals and foreign scientists by the office of

Conservacion Ecologica de los Recursos Naturales, Secretaria de Desarrollo Social (SEDESOL),

export permits from the office of Flora y Fauna Silvestres, Secretaria de Agricultura y Recursos

Hidraulicos (SARH), and environmental impact statements associated with government and private

development projects. This Act was reviewed in 1993 with the goal of providing more active

protection for endangered species.

In large part, conservation of the lesser long-nosed bat in Arizona is relatively straight-forward

because most major maternity roosts and many of the transitory roosts known are on Federally

owned lands (Organ Pipe Cactus National Monument, Cabeza Prieta National Wildlife Refuge, and

U.S. Forest Service) where a level ofprotection under section 7 exists. Old Manimon Mine, located

on the Tohono O’odham Nation, is a remote site whose protection by gating would be supported by

the tribe (A. Smith, pers. comm.). Colossal Cave, which housed a maternity roost until the 1960s,

has recently been modified to allowrecolonization by bats. Thus, no new land acquisition is needed

to protect known major Leptonycteris roosting sites, although this may change if additional roosts

are found off Federal lands. The provisions of the Mining Act of 1872 do complicate the issue of

protecting roosts in mines, or in areas that would be affected by mining, since the Federal agencies

may be restricted in denying or modifying some projects.

At least three major Leptonycteris roosts in Mexico, the Isla Tiburon Cave, Pinacate Cave, and Isla

San Andres Cave, are located in federally protected areas and are generally inaccessible to humans.

Others, as discussed earlier, are near to human settlements and while these roosts may not have been

disturbed in the past, societal changes in the human population could lead to disturbances in the

future and efforts to prevent such changes are very important.
23

Major food plants, columnar cacti and agave, are protected under the Arizona Native Plant Law

(A.R.S. Chapter 7, Article 1) by the State of Arizona. This law does not provide protection for these

species from all threats, but does prevent illegal harvest and promotes salvage ofspecimensin areas

where development is going to occur. The law does not go far enough to ensure that these plants

will be safeguarded in viable populations over the long term. The section 7 requirements ofthe Act

do provide a level of protection for these plants since their presence is required for the bats to

maintain their populations, but this protection is limited because oflack of knowledge ofwhat is

needed in foraging habitat to support the roost populations. There is likely a continuing loss of

forage plants and their habitat in Arizona and New Mexico because the protections available are not

sufficient to completely stop this loss.

Columnar cacti and agaves are not federally protected in Mexico; however, so major food plants

remain even more vulnerable to human disturbance. Destruction of columnar cacti is occurring

along the west coast ofmainland Mexico and Baja California with the construction ofresorts and

golf courses and in inland Sonora and Baja California Sur with the expansion of agriculture. The

local mescal industries continue to take large numbers ofagaves from the wild. Exactly what the

effects of this harvest are to the local agave populations and to the bats that depend upon them has

not been specifically determined; however, very few plant populations can cope with overharvest

over any significant length of time. What a safe harvest level for agaves might be has not been

determined. Loss of foraging habitat in Mexico is thus an important concern for the long term

stability and persistence ofbat populations.

In addition to protection of Leptonycteris roost sites and food plants in Arizona, this species is the

subjectofactive monitoring and research programsin Arizona,New Mexico, and Mexico. Programs

at Organ Pipe Cactus National Monument include several non-intrusive censuses ofthe Copper

Mountain roost annually, environmental monitoring ofthe roost, analysis offecal samples, and

assessment of the impact of low-flying military aircraft on bats. Additionally, work is beginning to

correlate bat arrival times with flowering offorage plant species on Organ Pipe Cactus National

Monument and in the Portal area near the Chiricahua Mountains in eastern Arizona. This is a

cooperative effort that includes the National Park Service and Bat Conservation International.

Annual censuses are conducted at the Bluebird Mine, the Pinacate Cave, Patagonia Bat Cave, and

State of Texas Mine. ScottAltenbach has been monitoring the activity ofLeptonycteris bats in the

Animas Mountains of New Mexico in recent years. Monthly censuses were conducted at the Isla

San Andres Cave in 1993-94. Surveys conducted in Saguaro National Monument and Ft. Huachuca

have identified roost sites for small populations ofL. curasoae. Conservation measures taken by the

Coronado National Forest in Arizona include setting standards and guidelines for the protection of

caves and roost sites, cave and mine protection, inventorying and monitoring activities, educational

activities, and protection of agave populations. Finally, foraging studies were conducted in 1993

near the Old Mammon Mine and on Cabeza PrietaWildlife Refuge. Fleming and his students and

collaborators are studying: the genetic structure of L. curasoae throughout its range (including

Venezuela) using DNA techniques; foraging behavior and its influence on the genetic structure of

columnar cacti atBahia Kino, Mexico; digestive physiology; diet using carbon and nitrogen stable

isotope techniques; and pollination biology and seed dispersal ofMexican columnar cacti.
24

II. RECOVERY

Objectives and Criteria

Ifthe most recent census numbers are correct, the lesser long-nosed bathas had a substantial increase

in numbers since the status surveys of 1984-85. Its population sizes appear to be far larger (by two

orders ofmagnitude in Arizona alone) than was known in 1985, and its numbers at some locations

appear to be relatively stable from year-to-year. As mentioned previously, there is some question

about the correctness of these numbers that requires additional investigation. We also do not know

where these additional bats came from. Is this an actual increase in numbers resulting from

successful recruitment of young to the adult population or is the increase the result of abandonment

of other roosts and thus higher occupancy ofthe remaining roosts or were these bats always present

but not located by earlier censuses? The Service cannot determine the answers, and the clear

disagreement between scientists familiar with the species only adds to the uncertainty about the

status of this species. The actual numbers ofthis species perhaps is a secondary consideration.

Regardless of actual numbers, because of its gregarious roosting behavior, this species will always

be vulnerable to catastrophic population loss through human disturbance of its roost sites. The

number of such sites, especially those that apparently can support large numbers of females and their

young, apparently is very limited. Loss of even one such site could eliminate a significant portion

ofthe total population and contribute to the extinction ofthe species.

Equal consideration must be given to protecting the habitat of the forage plant species essential to

the survival of this species. Maintenance ofroost sites without assuring that there will be viable

populations ofcolumnar cactus, Agave species and other food plants within an appropriate distance

does nothing to stabilize the status ofthe species and promote its recovery. The populations of

forage plants along migrationroutes is also an important consideration in the recovery ofthis bat.

This recovery plan outlines the steps necessary to downlist L. curasoae from endangered to

threatened. Recovery actions for the species stress protection of known roosts and feeding habitat

(including populations ofcolumnar cacti and paniculate agaves), population monitoring for a period

of at least 5 years at key sites throughout its known range, development of a public education

program on the beneficial aspects of bats in Arizona, New Mexico, and Mexico, and development

of a research program to answer questions critical for its management (e.g., What are the roost

requirements of this species? What are the foraging areas of specific roosts? What is its

reproductive cycle and mating system?).

The lesser long-nosed bat will be considered for downlisting when:

1. Each major roost population in Arizona and Mexico has been monitored yearly for at least five

years. Roosts to be monitored include the three major maternity roosts in Arizona (Copper

Mountain Mine, Bluebird Mine, and Old Mammon Mine) and three major “post-maternity”

roosts (Patagonia Bat Cave, State ofTexas Mine, and Hilltop Mines) and at least four major
25

roosts in Mexico (e.g., Pinacate Cave, Santo Domingo Cave, San Andres Cave, and Rancho

Tempisque Cave).

2. Results of the monitoring in #1 indicate that populations in all roosts have remained stable (+

10%) or have increased in size for a period of at least five years following approval ofthis

recovery plan. Population figures to be used as the baseline are the higher figures included in

this recovery plan.

3. Sufficient progress in the protection of both roosts and forage plant habitats that support those

roosts from disturbance or destruction must have been made.

4. No new threats to the species, its roost or foraging habitats, have been identified and currently

known threats have not increased significantly.

Achievement ofthe dowulisting criteriadoes not automatically mean the species will be downlisted.

The Service must consider all aspects of the status of the species before a decision is made to

downlist. These criteria are preliminary and may be revised on the basis of new information

obtained or developed during the implementation ofthe plan.

Step-down and Narrative Outline

1. Protect,monitor, and survey major roost sites

11. Protect known roost sites.

111. Administrative/management actions.

112. Physical protection.

113. Interagency cooperation.

114. Law enforcement.

12. Monitor roosts

121. Establish a monitoring protocol and schedule.

122. Establish a repository for census information.

13. Check historical roost sites and survey for new roosts

131. Ascertain status ofhistorically known roosts at appropriate times ofthe year

132. Survey likely areas in the U. S. and Mexico at appropriate times to locate new

roosts

2. Protect foraging areas and food plants

21. Determine the foraging areas and characteristics of those areas for representative

roosts

211. Describe landscape features ofsuitable foraging habitat.

212. Clarify role of lesser long-nosed bat in pollination and seed dispersal of forage

plant species.

213. Describe effects of human uses on populations of forage plants.

22. Administrative/management actions.
26

23. Interagency cooperation.

24. Law enforcement.

3. Public education

31. Design educational programs for the U. S. and Mexico

32. Implement the educational programs

4. Research.

41. Determine microclimate and physical conditions present in representative maternity

and non-maternity roosts at times of occupancy.

42. Determine the reproductive cycle and mating system of this species.

421. Determine the reproductive cycle.

422. Determine the mating system.

43. Determine normal behavior patterns.

431. Describe exit behavior and develop range of density figures for visual counts.

432. Describe migration and use patterns between roosts (both maternity to maternity

and maternity to post-maternity).

433. Describe factors involved with abandonment of roosts.

Narrative Outline for Recovery Actions

1. Protect, monitor~ and surveyinajnrmoslsites. This is the most important goal for continued

survival ofthe lesser long-nosedbat throughout its historic range. Proper protection of its major

roosts will ensure that this species will not go extinct. Accurate data on population trends are

needed, hence major roosts need to be monitored annually. Although many lesser long-nosed

bat roosts are known, it is likely that new ones (e.g., the State of Texas Mine in south-central

Arizona) will be found with additional surveying. Additional roosts undoubtedly occur in

Mexico. These should be located and protected.

11. ProtecLknownxroostslies. At least four major maternity roosts (Copper Mountain Mine,

Bluebird Mine, Isla Tiburon Cave, Pinacate Cave) and two other roosts (Isla San Andres,

Gruta Juxtlahuaca) are currently under Federal or local protection in the United States and

Mexico. Continued protection of these roosts is essential. Other important roosts in

Arizona(Old ManimonMine, Patagonia Bat Cave, State of Texas Mine, Hilltop Mines) and

Mexico (Santo Domingo Mine, Cueva “La Mina,” Rancho Tempisque Cave) should be

protected through appropriate legal channels.

111. Administrativeactions. Agencies should develop management plans for known

roosts that provide restriction or closures to human access during all times when bats

are present. Agencies should evaluate and implement protective mechanisms

available to them under State and Federal laws.
27

112. PhysicaLprotection. Iffound to be necessary by monitoring ofroost sites, protection

of roosts with gates and otherphysical barriers should be considered. It is important

that gating or fencing be “bat friendly,” i.e. should be easily traversed by bats and

should not unduly expose them to terrestrial or aerial predators.

113. Interagency cooperation. Communication between agencies and other interested

parties in the location and conditions at known or newly located roosts is essential.

It is especially important to keep roost visits to the minimum needed for monitoring.

A central repository for roost information, such as the Arizona Natural Heritage

database, would facilitate information exchange.

114. Law enforcement. Enforcement of all pertinent laws and regulations should be

provided all known roost sites.

12. Monitorroosts. Accurate annual censuses of important roosts are needed to determine

population trends in this bat. These roosts should include, but not be limited to, the

following: Copper Mountain Mine, Bluebird Mine, Old Mammon Mine, Patagonia Bat

Cave, State ofTexas Mine, Hilltop Mines, Pinacate Cave, Cueva del Tigre, Santo Domingo

Mine, Isla San Andres Cave, Cueva “La Mina,” Gruta de Juxtlahuaca, Rancho Tempisque

Cave.

121. DcveloiparnonlioringprotocuLancLscheduk. Accurate censustechniques need to be

developed that minimize disturbance to the bats but which provide reliable estimates

ofpopulation sizes. V. and D. Dalton are developing techniques using infrared video

equipment that may address some ofthese issues. Other methods should also be

evaluated. Alternate low-tech methods are needed for censusing most Mexican

roosts. Because ofthe fluidity ofpopulations ofthis bat, the scheduling ofannual

censuses at roosts is critical. Scheduling may need to be flexible enough to ensure

roosts are occupied at the time ofthe census.

122. Establislione or more locations for the deposition of annual census and othei

data. The conduct of annual censuses and other activities pertaining to this

species needs to be coordinated between appropriate U. S. and Mexican

agencies.

13. Check historical roost sites and survey rnew~roosts. Recovery ofthis species

requires that we have as much information as possible about the location and status

of active roosts ofthis species. Regularsurveys should be conducted to ascertain the

status ofhistorically used roosts and to locate new roosts.

131. Surveyliistoricallyi=nownroosts.Ifit does not already exist, a central database

ofknown roost sites needs to be established. These include, but should not be

limited to, roosts in Arizona, Sonora, and Baja California mentioned earlier in
28

this plan. These roosts should be visited at appropriate times ofthe year to

ascertain their use by L. curasoae. In visiting these roosts, care must be taken

to avoid unduly disturbing the bats.

132. Survey for new roosts. Itis likely that new roosts ofthis bat will be located in

the United States and Mexico. Preliminary surveys should be conducted in the

“off-season” whenmigrant bats are absent from their spring and summer roosts.

Presence ofpollen “splats” and cactus seeds and pulp are reliable indicators of

the use of a roost by Leptonycteris bats. Suspected roosts should be cautiously

revisited during the spring or summer.

2. Protect foraging areas and food plants. Columnar cacti and agaves provide critical food

resources for this bat. Populations ofthese plants need continued protection to sustain nectarfeeding bat populations. A critical needin this area is information about the size of the foraging

areas around roosts so that adequate areas can be protected. This information will indicate the

minimum area needed to support a roost ofnectar- and fruit-eating bats.

21. DciteminAheloragingareasandcharacterisficis ofthose~areasfor representative roosts

.

Radiotelemetry or other suitable techniques should be used to determine the foraging radius

ofroosts such as Copper Mountain Mine, Pinacate Cave, and Hilltop Mines. These studies

should involve tagging at least 15 randomly selected individuals at appropriate times ofthe

year.

211. Describe landscape features ofsuitable foraging habitat. Information on densities of

forage plants, spatial relations between areas identified as used by bats and timing of

food availability should be collected to assess the need to protect or manage forage

plant habitat to provide adequate forage opportunities.

212. Clarify the role ofthe lesser long-nosed bat in pollination and seed dispersal in forage

plantspecies. Although much is known about the role this species plays, there is an

ongoing controversy that should be addressed. Resolution of this issue would

contribute to the development offorage plant management plans.

213. Describeeffects of human uses on populations of forage plants. The loss or decline

in forage plant populations due to urban development, livestock grazing, recreation,

harvest for commercial purposes (examples are sale of cacti and use of agave heads

for mescal production), introduction of non-native plant species and other factors is

a significant threat to the long-term stability of lesser long-nosed bat populations.

Effects to foraging areas around roosts and along migratory paths should both be

considered in this evaluation.

22. Administrative/management actions. Federal and State agencies should develop long-term

strategies to maintain the health of columnar cactus and agave populations on their lands.
29

Development ofstandards that assess the likely importance ofspecific plant stands as a food

resource forfruit eating bats would facilitate management planning in areas around roost

sites. Agencies should evaluate and implement protective mechanisms available to them

under State and Federal law.

23. Interagenciyxooperation. Communication between agencies and other interested parties on

issues related to food plants, especially the effects ofmanagement actions and condition and

distribution of food plants, is essential to maintain the viability ofthe resource. Information

on continuing losses to forage habitat should be compiled by agencies in a common

repository.

24. Law enforcement. Enforcement ofall pertinent laws and regulations will provide some

level ofprotection forfood plants. Additional legal protection for forage plants, especially

in Mexico, should be sought.

3. Pjubliceducatinn. While the “image” ofbats has improved greatly in the U.S. in recent years,

thanks largely to the efforts of Bat Conservation International, much can still be done to present

bats in general, and the lesser long-nosed bat in particular, as beneficial and interesting members

of arid habitats in the United States and Mexico. Visitor centers at Organ Pipe Cactus National

Monument, Cabeza Prieta Wildlife Refuge, Chiricahua National Monument, and Cave Creek

Recreational Area should devote space to a Leptonycteris-cactus or -Agave exhibit to inform

people about this aesthetically beautiful and biologically important interaction between bat and

plant. Efforts to develop a program in bat education in Mexico should be accelerated. A

cooperative effort between Bat Conservation International and appropriate Mexican

conservation and educational agencies should be encouraged to develop educational materials

(e.g. posters and booklets) for use in primary and secondary schools. Those areas housing large

roosts of Leptonycteris bats (e.g. Bahia Kino, Alamos, and Aduana in Sonora; Chamela and

Ajiijic in Jalisco; and Rancho Tempisque in Chiapas) should be specially targeted for the

distribution ofthese materials. An informed public is essential for conserving bats, their roosts,

migratory pathways and forage plants.

31. Designed~ucational programs for the u.S. and Mexico. In the U.S., this task should involve

a cooperative effort between state and federal agencies and Bat Conservation International

(BCI). A similar cooperative effort needs to be established between appropriate Mexican

federal and state agencies and BCI.

32. Implement the educationaLprograms. Educational programs are only ofuse if completed

and presented to the public. Agencies and other involved parties should take the necessary

steps to provide this information to the public.
30

4. Research. Several aspects ofthe biology and habitat preferences of L. curasoae currently are

incompletely or poorly known. This information is necessary for making informed decisions

concerning the conservation ofthis bat and management ofits critical resources.

41. Determine the microclimatic and physical conditions present in representativeinaternityand

pisv-lnaternityrnost&attimesnLoccupancy. Leptonycteris bats occupy some caves and

mines but not others. We currently do not understand how different physical and biological

factors influence roost choice in this bat. A comparison ofthe physical features ofoccupied

and unoccupied (or abandoned) roost sites could help to answer questions regarding roost

choice. We need to know much more about factors that are responsible for changes in roost

use to understand the dynamics ofL. curasoac populations.

42. Determine the reproductive cycle and mating sy~temofthissnecies. The reproductive cycle

and mating system ofthis bat is not yet known. This information is crucial for determining

the reproductive potential and genetic structure ofthe species. Determination of mating

sites in the U. S. and Mexico is critical for developing a realistic conservation plan for this

bat.

421. Determine the reproductive cycle. We need answers to the following questions. Do

females residing in Mexico and the U.S. give birth to one or two young per year?

How long do females and their recent offspring remain together? Do females and

their recent offspring migrate together or independently? How do young bats learn

migratory routes?

422. Determine the mating system. Currently unanswered questions include: where does

mating take place and what is the form of the mating system? Are adult males

sexually active year-round? How does the mating system influence the genetic

structure of this bat within and between roosts?

43. Determine normal behaviorpatterns. There are several aspects of behavior that are unclear

or unknown. Development of appropriate census techniques and management plans for

roosts require that we understand how the bats use these areas.

431. Describe exit behaviorand.develop range of density figures for visual counts. There

is a question as to how bats leave the roost to forage. Whether there is or is not

“swirling” at the entrance to the roost can greatly influence counts. Different roosts

may also have different exit patterns. There is information on densities of bats in the

roosts, but itwould be useful to refine these figures for use in census efforts. Declines

orincreases in bat populations cannot be documented without accurate census data.

432. Describe migration and usepattern~betweenrQosts4lotlLmaternitylolnatemityand

maternityiopost-maternity). Movements ofbats between roosts clearly occurs, but

it is not clear where bats in a particular roost came from. Knowing this information
31

would assist in determining effects ofactions that may affect one or another roost,

clarify census counts, and development of management plans for roosts and forage

plant habitats.

433. Describe factors involved with abandonment ofroosts. How and why bats abandon

roosts is partially understood, but additional information on the threshold level of

disturbance needed to refine management of roosts and determine levels of

disturbance that can be allowed for research. Other factors that need to be examined

are the timing of the disturbance, types of disturbances, and the time needed to

recolonize an abandoned roost. Understanding how bats use roosts in concert with

each other will contribute to this research.
32

III. Literature Cited

Alavarez, T., and L. Gonzalez Q. 1970. Analisis polinico del contenido gastrico de murcielagos

Glossophaginae de Mexico. An. Esc. Nac. Cienc. Biol., Mexico 18: 137-165.

Arends, A., F. J. Bonaccorso, and M. Genoud. 1995. Basal rates ofmetabolism of nectarivorous

bats (Phyllostomidae) from a semiarid thorn forest in Venezuela. J. Mammal. 76: in press.

Arita, H. T. 1991. Spatial segregation in long-nosed bats, Leptonycteris nivalis and Leptonycteris

curasoae, in Mexico. J. Mammal. 79: 706-714.

Arita, H. T. 1993. Conservation biology ofthe cave bats of Mexico. J. Mammal. 74: 693-702.

Arita, H. T., and S. R. Humphrey. 1988. Revision taxonomica de los murcielagos magueyeros del

genero Leptonycteris (Chiroptera: Phyllostomidae). Acta Zool. Mexicana, n.s., 29: 1-60.

Avise, J. C. 1989. Gene trees and organismal histories: a phylogenetic approach to population

biology. Evolution 43: 1192-1208.

Bonaccorso, F. J., A. Arends, M. Genoud, D. Cantini, and T. Morton. 1992. Thermal ecology of

moustached and ghost-faced bats (Mormoopidae) in Venezuela. J. Mammal. 73: 365-378.

Cockrum, E. L. 1991. Seasonal distribution of northwestern populations ofthe long-nosed bats,

Le~nonycteris sanborni Family Phyllostomidae. Anal. Instit. Biol;. Univ. Nac. Autonoma de

Mexico, Ser. Zool. 60 181-202.

Cockrum, E. L., and E. Ordway. 1959. Bats of the Chiricahua Mountains, Cochise County,

Arizona. Amer. Mus. Novitat. 1938: 1-35.

Cockrum, E. L., and Y. Petryszyn. 1991. The long-nosed bat, Leptonycteris: an endangered species

in the southwest? 0cc. Pap. Mus. Texas Tech Univ., 142: 1-32.

Dalton, V. M., and D. C. Dalton. 1993. Assessment ofthe impacts oflow level military aircraft on

Leptonycteris curasoae, an endangered bat, at Organ Pipe Cactus National Monument, Arizona.

Final Report. Prepared for Organ Pipe Cactus National Monument and 58th Civil Engineering

Squadron, Luke Air Force Base. 54 pp.

Easterla, D. A. 1972. Status ofLeptonycteris nivalis (Phyllostomatidae) in Big BendNational Park,

Texas. Southwest. Nat. 17: 287-292.

Fleming, T. H. 1986. Opportunism vs. specialization: the evolution of feeding strategies in

fr~givorous bats. Pp. 105-118 in A. Estrada and T. H. Fleming (eds.) Frugivorous and seed

dispersal. W. Junk. Dordrecht, Netherlands.
33

Fleming, T. H. 1988. The short-tailed fruit bat. Univ. ofChicago Press, Chicago, Illinois.

Fleming, T. H. 1993. Plant-visiting bats. Amer. Sci. 8 1(5): 460-467.

Fleming, T. H., R. A. Nunez, and L. S. L. Steinberg. 1993. Seasonal changes in the diets ofmigrant

and non-migrant nectarivorous bats as revealed by carbon stable isotope analysis. Occologia

94: 72-74.

Fleming, T. H., M. D. Tuttle, and M. A. Horner. 1995. Pollination biology and the relative

importance of nocturnal and diurnal pollinators of three species of Sonoran Desert cacti.

SouthwesternNat.: in press.

Hayward, B., and E. L. Cockrum. 1971. The natural history of the western long-nosed bat,

Leptonyciteris sanborni. West. New Mexico Univ., Res. Sci. 1: 75-123.

Heacox, K. 1989. Fatal attraction? Internat. Wildlife 19(3): 38-43.

Hofffiieister, D. F. 1957. Review ofthe long-nosed bats ofthe genus Leptonycteris. J. Mammal.

38: 454-461.

Hoffmeister, D. F. 1986. Mammals ofArizona. University of Arizona Press, Tucson. 602 pp.

Howell, D. J. 1974. Bats and pollen: physiological aspects ofthe syndrome of chiropterophily.

Comp. Biochem. Physiol. 48: 263-276.

Howell, D. J. 1976. Plant-loving bats, bat-loving plants. Nat. Hist. 85(2): 52-59.

Howell, D. J. 1979. Flock foraging in nectar-feeding bats: advantages to the bats and to the host

plants. Am. Nat. 114: 23-49.

Howell, D. J. 1991. The long-nosed bat, Leptonycteris: an endangered species in the southwest!!

Unpubl. manuscript.

Howell, D. J. 1994. Foraging patterns and diet ofLeptonycteris curasoae in southwestern Arizona.

Air Force Contract #F02604 92C0028 Report. 39 pp.

Howell, D. J., and B. S. Roth. 1981. Sexual reproduction in agaves: the benefits ofbats: cost of

semelparous advertising. Ecology 62: 3-7.

Hoyt, R. A., J. S. Altenbach, and D. J. Hafner. 1994. Observations on long-nosed bats

(Leptonycteris) in New Mexico. Southwest. Nat. 39: 175-179.
34

McGregor, S. F., S. M. Alcorn, and G. Olin. 1962. Pollination and pollinating agents ofthe

Saguaro. Ecology 43: 259-267.

Nabhan, G. P., and T. H. Fleming. 1993 The conservation ofmutualisms. Conserv. Biol. 7: 457.

Nassar, J. 1991. Biologia reproductiva de cuartro cactaceas quiropterofilas venezolanas (Cereceae:

Stenociereus gnseus, Pilosocereus moritzianus, Snhpilocereus riepandus y S. horrispinus), y

estragias de visita de los murcielagos asociados a estas. Tesis Bachillerato, Departamento de

Zoologia, Universidad Central de Venezuela, Caracas, Venezuela.

Petit, 5. 1995. The mutualism between bats and columnar cacti on Curacao and its conservation

implications. Ph.D. dissertation, University of Miami.

Quiroz, D. L., M. S. Xelhuantzi, and M. C. Zamora. 1986. Analisis palinologico del contenido

gastrointestinal de los murcielagos Glossophaga soricina y Leptonycteris yerbahuena de las

Grutas de Juxtlahuaca, Guerrero. Instit. Nac. antrop. Histor. Serie Prehistoria, 1-62.

Sahley. C. T., M. A. Horner, and T. H. Fleming. 1993. Flight speeds and mechanical power outputs

in the nectar feeding bat, Leptonycteris curasoae (Phyllostomidae: Glossophaginae). J.

Mammal. 74: 594-600.

Shull, A. M. 1988. Endangered and threatened wildlife and plants; determination ofendangered

status for two long-nosed bats. Fed. Register 53 (190): 38456-3860.

Sidner, R., and R. Davis. 1988. Records of nectar-feeding bats in Arizona. Southwest, Nat. 33:

493-495.

Tuttle, M. D. 1994. The lives of Mexican free-tailed bats. Bats 12 (3): 6-14.

Tuttle, M. D., and D. Stevenson. 1982. Growth and survival ofbats. Pp. 105-150 in t. Kunz (ed.)

Ecology ofbats. Plenum Press, New York.

U. S. Fish and Wildlife Service. 1994. Mexican long-nosed bat (Leptonycteris nivalis) recovery

plan. U. S. Fish and Wildlife Service, Albuquerque, New Mexico. 91 pp.

Valiente-Banuet, A., M. del Coro Arizmendi, A. Rojas-Martinez, and L. Dominguez-Canseco.

1995. Geographic and ecological correlates between columnar cacti and nectar-feeding bats in

Mexico. J. Trop. Ecol.: in press.

Wilkinson, G. S., and T. H. Fleming. 1995. Migration routes and evolution oflesser long-nosed

bats, Leptonyctens curasaoe, inferred from mitochondrial DNA. Molecular Ecology: in press.
35

Wilson, D. E. 1979. Reproductive patterns. Pp. 3 17-378 in Baker, R. J., J. K. Jones, Jr., and D. C.

Carter (eds.), Biology ofbats oftheNew World family Phyllostomatidae. Part III. Spec. Publ.

Museum, Texas Tech Univ. No. 16.

Wilson, D. E. 1985. Status report: Leplonyciteris sanhorni Hoffmeister, Sanborn’s long-nosed bat.

U.S. Fish and Wildlife Serv., Denver Wildlife Res. Center, Nat. Mus. Nat. Hist., Washington

D.C., 35 pp.
36

IV. List ofContacts

UNITED STATES

Arizona Game and Fish Department: Non-Game Branch

2221 W. Greenway Road, Phoenix, Arizona 85023-4399

Dr. Scott Altenbach and Dr. James Findley

Department ofBiology, University ofNew Mexico, Albuquerque, New Mexico 87131

Dr. Virginia M. Dalton and Mr. David C. Dalton

1468 N. Westridge Ave., Tucson, AZ 85745

Dr. E. Lendell Cockrum, Dr. Var Petryszyn, and Ms. Ronnie Sidner

Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721

Dr. Ted Fleming

Department ofBiology, University ofMiami, Coral Gables, FL 33124

Dr. Donna J. Howell

Directorate ofEnvironment, Natural Resources, Bldg. 1105, Forrest Road, Ft. Bliss, Texas 79916.

Dr. Merlin D. Tuttle

Bat Conservation International, P.O. Box 162603, Austin, TX 78716

Dr. Pat Brown

134 Wilkes Crest, Bishop, California 93514

Dr. Donald Wilson

Smithsonian Institution, 10th and Constitution Avenue, NW, NHB-MRC180, Washington, D.C.

20560

MEXICO

Dr. Hector T. Arita, Dr. Gerardo Ceballos, and Dr. Rodrigo Medellin

Centro de Ecologia, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-275, C.P.

04510 Ciudad Universitaria, Mexico

Dr. Enriqueta Velarde

Director General de Flora y Fauna Silvestre, Secretaria de los Recurso Naturales, Secretaria de

Desarrollo Social, Rio Elba #20 Piso 10, Colonia Cuauhtemoc, 06500 Mexico City, Mexico
37

Lic. Roberto Calleja Ortega

Director General de Flora y Fauna Silvestre, Secretaria se Agricultura y Recursos Hidraulicos,

Avenida Nuevo Leon #210, Piso 19, C.P. 03100, Colonia Ex-Hipodromo-Condesa, Mexico City,

Mexico

Ing. Edgar Gonzalez

Director, Direccion de Education Ambiental, Rio Elba #20, Piso 7, Colonia Cuauhtemoc, 06500

Mexico City, Mexico
38

V. Implementation Schedule

The following implementation schedule outlines actions and costs for the lesser long-nosed bat

recovery plan. It is a guide for meeting the objectives discussed in Part II ofthis plan. The schedule

indicates task numbers, priorities, durations and estimated costs. These tasks, if accomplished,

should enable the downlisting ofthis species to threatened. The levels offunding contained in the

implementation schedule are estimates. Actual funding needs will have to be calculated at the time

an element ofthe plan is implemented. Inclusion ofthese numbers in the plandoes not commit any

agency to expend these funds.

This list contains some agencies or groups that may be involved in implementation ofthis recovery

plan. Because ofthe large range ofthe species, most ifnot all, identified parties would be involved

in some way in the implementation ofany specific element ofthe plan. For this reason there is no

“Lead Agency” column in the implementation schedule. It can be assumed that the Arizona

Ecological Services Office ofRegion 2 ofthe Fish and Wildlife Service will act as the lead agency

in the United States when necessary, or will delegate that role to one ofthe other involved parties

for specific tasks. Coordination with cooperating agencies and groups in Mexico may be

accomplished through several avenues. In addition to the groups listed below, researchers from

several universities in the United States and Mexico will contribute to the recovery effort.

U.S. Fish and Wildlife Service

Bureau ofIndian Affairs

Bureau ofLand Management

National Park Service

U.S.D.A. Forest Service

Department ofDefense

Arizona Game and Fish Department

Arizona Department of Agriculture

Secretaria de Agricultura y Recursos Hidraulicos, Flora y Fauna Silvestres (Mexico)

Secretaria de Desarrollo Social, Instituto Nacional de Ecologia (Mexico)

Tohono O’Odham Nation

Bat Conservation International

Priorities in Column 2 ofthe following Implementation Schedule are assigned as follows:

Priority 1 -- An action that must be taken to prevent extinction or to prevent the species from

declining irreversibly in the foreseeable future.

Priority 2 -- An action that must be taken to prevent a significant decline in species

population/habitat quality or some other significant negative impact short of

extinction.

Priority 3 -- All other actions necessary to provide for full recovery ofthe species.
39

In the duration column, numbers are years needed to complete the task. A continuing task (cont.)

will continue once implemented. An ongoing task (ongo.) is already being implemented.
Iinplemcntation Schedule

Costs (thousands of dollars)

Task Priority Duration FY96 FY97 FY98 FY99 FY20 Total

111 1 cont. 20 20 5 5 5 55

112 2 cont. 2 2 2 2 2 10

113 2 cont. 2 2 2 2 2 10

114 1 ongo. 5 5 5 5 5 25

121 1 2 15 15 - - - 30

122 2 1 10 - - - 10

131 1 5 50 50 50 50 50 250

132 2 5 20 20 20 20 20 100

211 1 5 20 20 20 20 20 100

212 3 5 10 10 10 10 10 50

213 2 5 20 20 20 20 20 100

22 1 cont. 5 5 5 10 10 35

23 2 cont. 2 2 2 2 2 10

24 1 cont. 5 5 5 5 5 25

31 3 2 10 10 2 2 2 26

32 3 cont. 2 2 2 2 2 10

41 2 2 - - 20 20 - 40

421 2 2 15 15 - - 30

422 2 2 10 10 - - 20

431 2 2 10 5 15

432 2 3 - - 20 20 20 60

433 1 5 10 10 10 10 10 50

Total 243 228 200 205 185 1061
42

Appendix A. Public Review

The availability ofthe draft recovery plan for public review was advertised in the Eederal Register

on January 4, 1994, with copies mailed beginning on January 12. A 60-day public comment period

was provided. Seventeen letters of comment and two annotated copies ofthe draft were received.

The list of commenters follows:

Federal agencies

Mr. Louis Volk, USDA Forest Service, Albuquerque, New Mexico

Mr. Robert X. Barry, Luke Air Force Base, Arizona

Mr. Tony Maciorowski, Environmental Protection Agency, Washington, D.C.

Mr. Vernon Palmer, Phoenix Area Director, Bureau ofIndian Affairs, Phoenix, Arizona

Mr. James A. Barber, Papago Agency, Bureau ofIndian Affairs, Sells, Arizona

Mr. Lester Rosenkrance, State Director, Bureau ofLand Management, Phoenix, Arizona

Mr. Ron Nowak, Fish and Wildlife Service, Washington, D.C.

Ms. Laura Thompson Olais, Cabeza Prieta National Wildlife Refuge, Fish and Wildlife

Service, Ajo, Arizona**

Mr. R. Clay Cummingham, General Superintendent, Southern Arizona Group, National Park

Service, Phoenix, Arizona

State or local agencies

Mr. Duane Shroufe, Director, Arizona Game and Fish Department, Phoenix, Arizona

Mr. William C. Scalzo, Director, Maricopa County Parks and Recreation Department, Phoenix,

Arizona

Private citizens

Dr. Virginia Dalton and Mr. David Dalton, Tucson, Arizona

Ms. Pamela Pride Eaton, The Wilderness Society, Washington, D.C.

Dr. Donna Howell, Tucson, Arizona (two letters)

Ms. Sarah Schmidt, Portal, Arizona

Ms. Eleanor G. Wootten, Friends ofBats of New Mexico, Las Cruces, New Mexico

Mexico

Dr. Oscar Sanchez Herrera, Director de Flora and Fauna Silvestres

Dr. Rodrigo A. Medellin, Centro de Ecologia, Universidad Nacional Autonoma de Mexico**

Dr. Enriqueta Velarde, Instituto Nacional de Ecologia

** provided comments written on the draft, these were incorporated as appropriate.
43

Appendix B. Letters ofComment

All personal letters of comment are reproduced in this Appendix. All comments were reviewed and

considered in finalizing the recovery plan. Responses to comments were dealt with in two ways: (1)

editorial comments and corrections offactual errors were incorporated directly into the text ofthe

plan; or (2) comments concerning plan content were addressed in specific responses, although

similar comments were grouped together and answered as one. These specific responses are given

in Appendix C. Numbers in the margins ofthe letters of comment in this appendix refer to the

appropriate response given in Appendix C.
44

Translation ofletter of comment from Dr. Velarde.

I refer to your letter requesting comments on the lesser long-nosed bat Leptonycteris curasoac

yerbabuenae.

The particular comments follow. First, accept my apology for sending the information after the

requested date owing to the situation that I requested the opinion of a Mexican specialist about the

recovery plan forthe lesser long-nosed bat who had the following comments.

- The information with regard to yourplan is very well based by the study ofthe populations of

Arizona and New Mexico and to a lesser extent for the populations of Sonora and Baja

California, but practically nothing for the populations in the rest of Mexico that comprise the

major part ofthe distribution ofthe species, for which reason it is necessary to study without

delay the fluctuations in bat populations. I am in agreement with the authors that the species is

not in danger of extinction.

- Additionally, the above mentioned plan does not mention any concrete action forthe protection

ofthe species, since protecting the vegetation that provides foods and the sites ofrefuge is very

difficult owing to the distribution ofthe species which encompasses at least all the Pacific slope

of Mexico and to protect all this area is not realizable, for this reason it would be better to

establish areas or strategic points where you can accomplish a real and effective protection of

the environment.

- Based on the above, the “Direcci6n General “is analyzing the strategic areas for your study. It

is in this sense, that I solicit information from you regarding the feasibility of your agency

exploring the possibility ofobtaining economic aid with the purpose ofinstrumenting the above

plan for Mexico for which reason we would propose a Mexican specialist who in coordination

with you could bring about this multifaceted plan.

Without other particulars, I reiterate my most distinguished consideration.

Dr. Enriqueta Velarde
45

Appendix C. Responses to Comments

1. The Service appreciates your interest and cooperation in the development and implementation

ofthe recovery plan for the lesser long-nosed bat.

2. Comments have been incorporated into the plan where appropnate.

3. The intent of item 121 in the step-down outline (item 2 in the final recovery plan) is to

highlight the importance of healthy, self-sustaining populations offood plants, especially those

within the foraging area ofa roost. While general “ecosystem management” may be sufficient

to address these issues over the large scale, there may be localized situations that require

specific management actions or plans. Such issues could include prescribed burning, livestock

grazing, recreational opportunities, land development or mining.

4. The maps showing the range and important roosts ofthe lesser long-nosed bat have been

included in the final recovery plan. The Service does not believe that location data provided

in these maps is too specific or presents a risk to the bat.

5. Many comments were received concerning the appropriateness oflisting the lesser long-nosed

bat as an endangered species. These comments focused on the difference in opinion between

scientists familiar with the species on the size ofpopulations associated with known roosts.

The Service is required to list species based on the best scientific and commercial information

available at the time the listing is developed. At the time the species was listed, available

information stated that populations were low. Since that time, additional information has been

presented on the numbers of bats using the known roosts that indicate populations may be

larger than previous data suggested. These figures remain a source ofcontroversy within the

scientific community.

The Service stands by its listing of the lesser long-nosed bat. Even if population sizes are

larger, the number ofmajorroosts remains small and loss of any major roost sites, especially

maternity roosts, could have serious effectsto species survival regardless ofthe number ofbats

in a particular roost. The final recovery plan attempts to deal with the controversy by

recommending additional monitoring ofroosts and research to address other threats.

6. Some early work on the lesser long-nosed bat resulted in staged photographs ofbats and Agave

schnittii. Information since then indicates that bats do not use this agave species as a food

source in the wild. Research has shown that A. pailmeri, A. parryi, and A. deserti, all paniculate

agaves, are three ofthe main food plants in the United States.

7. Information was correctly stated in the draft.
46

8. The question of population size has been addressed in comment response #4. The Service

recognizes the need for additional inventory work to locate additional roosts and this is

included in the step-down outline. The Service does not believe that the biology or status of

this species is sufficiently known to justify delisting at this time. A fuller understanding ofthe

place of the lesser long-nosed bat in the Sonoran desert is needed before delisting can be

justified.

9. The purpose ofthe proposed item is covered in item 12.

10. Photographs are difficult to reproduce under standard photocopying processes. A drawing of

the lesser long-nosed bat is on the cover ofthe recovery plan.

11. Night roosts are essential for the lesser long-nosed bat; however, they are likely not a limiting

factor in the use of an area. Qualifications fora suitable night roost are flexible, with buildings,

caves not used as day roosts, crevices, and trees recorded as being used.

12. Dr. Yar Petryszyn hasobserved lesser long-nosed bats drinking water and making captures over

water have been made in at least two locations. It is not known how often these bats drink, or

how critical free water is to them. Nectar contains a great deal of water; however, the high

osmotic potential may cause physiological problems and bats may drink water to correct this.

More information is needed to fully answer this.

13. The development ofthis recovery plan provides an opportunity for all interested parties to

continue their participation in the recovery ofthe lesser long-nosed bat. Because oflimited

Federal funding, input by knowledgeable persons to the recovery ofthe species should not be

discouraged, however, the Service agrees that there is a need to better coordinate all activities

regarding this species.

14. The Service does not believe a second draft ofthis recovery plan is needed. Several ofthe

issues referred to by Arizona Game and Fish Department reflect the existing controversy about

the status and role ofthe bat in the Sonoran Desert and throughout its range. Revisions to the

plan after the public comment period were made to address concerns expressed. However, the

basic strategy to identify the types of actions that would be needed to recover the species did

not significantly change. Because ofthis, the Service believes the species would be better

served by issuing a final recovery plan at this time.

15. The final plan includes recommendations for monitoring, surveys and research in both the

United States and Mexico. The United States does not have authority over activities in Mexico

that may affect the species. We can only attempt to develop cooperative ventures between the

two countries that would foster the recovery ofthis species.

16. Figure 2 was provided to highlight the known roosts in Arizona. “Major” roosts are defined

as those where the lesser long-nosed bat can reliably be found.
47

17. Table 3 has been modified to indicate transitory or male roosts. Population estimations are

made using only maternity roosts.

18. In this discussion, the size ofthe roost is less important than the presence or absence oflesser

long-nosed bats asthat was an important factor in the listing ofthe species. Estimates oftotal

population size in the recovery plan are based on adults only, and populations in transitory

roosts are not included.

19. Specific data on roost populations near humanpopulation areas are limited. No rigorous counts

have been made at the San Domingo Mine near Alamos, Sonora. However, this roost has

supported substantial numbers of bats for many years. We do not know if the population

declined before the period ofobservation, all that can be said is that no significant increases or

decreases have been observed.

20. Recovery plan format requires a “Reasons for Listing” section. In this recovery plan, the

Service has chosen not to simply restate the arguments put forward in the original listing.

There has been considerable discussion between scientists about the population and status of

this species since the listing became final. The Service believes that the ideas and issues in

those discussions should be available in a public document. The Service stands by its decision

to list the species as endangered, and hopes that the implementation ofthe recovery plan will

provide for the acquisition of new information that would assist in resolving these issues.

21. The recovery plan is now focused on the strategy needed to downlist the lesser long-nosed bat

to threatened from endangered. Criteria to delist the specieswill be developed after the species

has been downlisted to threatened. Before a decision to downlist or delist any listed species

is made by the Service, a thorough review ofthe species status, protection, threats and other

pertinent information is made. Downlisting upon meeting the criteria in a recovery plan is not

automatic.

22. The recovery plan does not minimize the potential risk to the lesser long-nosed bat from human

disturbance ofroosts. Given the limited number ofroosts, the loss of even one major roost

could have significant adverse effects on the species. The acknowledgement that an effect

exists does not preclude incorporation in the plan ofinformation indicating that the effect may

not have happened at some roosts.

23. The issue of military aircraft overflights as a threat to the stability of roosts, especially

maternity roosts, has been addressed in the recovery plan. The detailed evaluation requested

in this letter of comment is more appropriately addressed under inter-agency Section 7

consultation. A recently completed study by Dr. Virginia Dalton and Mr. David Dalton was

funded by the U.S. Air Force to provide a first step in answering questions about aircraft noise

and bats. This study was conducted at the maternity roost on Organ Pipe Cactus National

Monument. The researchers found that there was a small but statistically significant reduction

in the number of bat flights in the roost during the overflight, but there was no statistically
48

significant difference in falling non-volant young, panic flight or startle response. Normal bat

flight levels were reached in less than 30 minutes after the overflight. Clearly, what is true at

one site may not be true at anotherbecause ofphysical differences in the site location and other

factors. Because of site differences, it may not be possible to define a control group as

suggested in the comments. The Service believes additional work would be useful in refining

the effects ofaircraft noise; however, we believe the appropriate venue is through Section 7.

The Service will work with the U.S. Air Force and othermilitary organizations to addressthis

issue.

24. It is not the intention ofthe Service to act as mediator between the members ofthe scientific

community who disagree about the status ofthe lesser long-nosed bat. As noted in comment

#4 ofthis appendix, the Service recognizes that there is a need to address these contentious

issues and resolve them so that recovery ofthe bat can proceed. That is the purpose ofthis

recovery plan. The Service and its contractor, in revising the plan, have removed or modified

statements that may have been seen as inappropriate given the existing disagreements. In the

final plan, the Service has attempted to recognize the differing points of view ofthe scientific

community. No one, including the Service and its contractor, intended to defame, insult, or

impugn any member of the scientific or professional community in the production ofthis

recovery plan. The Service also recognizes that there are going to be many comments and

statements which cannot be incorporated into the plan without one or another ofthe parties

disagreeing with that inclusion. The fact that all letters of comment are reproduced in their

entirety in this recovery planwill assist the public and agencies in understandingthe parameters

ofthese issues.

25. Since the lesser long-nosed bat was listed as an endangered species throughout its range, the

existence of bat populations in Mexico is important to the status ofthe species and should be

considered. There may or may not be a relationship between these populations that needs to

be investigated.

26. The location of“new” roosts is indeed an artifact ofthe increased efforts to locate a species

once it has been listed. Without specific information about the location and previous

populations of “old” abandoned roosts, it is difficult to say if the “new” roosts are actually

“new” in the sense ofthis comment. For example, the State ofTexas Mine was first discovered

to have lesser long-nosed bats in 1992, and has been occupied each year since. There is some

limited anecdotal information that indicates bats ofsome sort used the mine prior to 1992, but

no actual surveys were done.

27. Dr. Gary Nabhan ofthe Arizona-Sonora DesertMuseum was contacted for clarification ofthe

statements attributed to him both in the draft recovery plan and in the letter of comment. Dr.

Nabhan states that his research indicates that while two million agave heads or “ramets” are

removed by harvesters in Sonora each year, in only a few (two or three) places have the agave

populations been overharvested to an extent that agaves are extremely rare. Even in those

areas, small numbers ofagaves persist in inaccessible locations and contribute nectar and pollen
49

to the bats using the area. Dr. Nabhan confirmed that in harvest areas, vegetative reproduction

may occur at a higher rate than sexual reproduction because ofthe removal ofthe flower stalk.

The entire “genet,” or genetic individual, is not lost and the opportunity to flower has been

delayed but not eliminated. There is likely to be some effect to the lesser long-nosed bat ofthe

two million ramets per year harvest over the 300 miles of migratory pathway in Sonora. Dr.

Nabhan states that the magnitude and significance ofthe effect is not known but should be

considered in evaluating long term management strategies.

28. In terms ofproviding for the management oflesser long-nosed bat food resources, additional

information is needed on preferred density offood plants, optimum foraging distances, age

structure of the plant populations, and effects of other human activities on sustainable

populations ofthese plants. Some ofthese may require bats to be used in answering these

questions, some will not.

29. The lesser long-nosed bat was listed as an endangered species throughout its range. All

populations are thus ofsignificance in the recovery ofthis species. The stress in this recovery

plan is on the United States and northern Mexico because there is a link between these areas.

Other issues and problems may affect populations ofthis species in otherparts of Mexico. The

Service has attempted to address this larger issue by including tasks in the step-down outline

to encourage international discussions on the status and recovery ofthis species.

30. The Arizona cliffrose is a very detailed and specific plan for a species with a limited range and

quantifiable threats. This is not the case with the lesser long-nosed bat. The Service has

elected to be more general in this plan; however, the items and issues suggested in the letter of

comment will be considered during implementation ofthe plan.